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1. 
   “Green” Fluorescent–Plasmonic Carbon-Based Nanocomposites with Controlled Performance for Mild Laser Hyperthermia , vol. 10, N11, pp. 1229, (2023)
   аннотация

   
   Fluorescent carbon nanodots are a promising nanomaterial for different applications in biophotonics, sensing and optical nanothermometry fields due to their strong fluorescence properties. However, their multi-modal applications are considerably limited, requiring the use of several nanoagents that could solve different tasks simultaneously. In this paper, we report the first experimental results on a facile “green” laser-based synthesis of multi-modal carbon–metallic nanocomposites with tuned optical performance. This simple approach leads to the appearance of finely controlled plasmonic properties in carbon-based nanocomposites whose spectral position is adapted by using an appropriate material. Thus, longer laser ablation provokes 29-fold increase in the absorption intensity of carbon–gold nanocomposites due to the increase in the metal content from 13% (30 s) to 53% (600 s). Despite strong plasmonic properties, the metal presence results in the quenching of the carbon nanostructures’ fluorescence (2.4-fold for C-Au NCs and 3.6-fold for C-Ag NCs for 600 s ablation time). Plasmonic nanocomposites with variable metal content reveal a ~3-fold increase in the laser-to-heat conversion efficiency of carbon nanodots matching the temperature range for mild hyperthermia applications. The findings presented demonstrate a facile approach to expanding the properties of chemically prepared semiconductor nanostructures due to the formation of novel semiconductor–metallic nanocomposites using a “green” approach. Together with the ease in control of their performance, it can considerably increase the impact of semiconductor nanomaterials
   
2. MIROSLAVA FLIMELOVA
   AN IMPACT OF THE LASER IRRADIATION TIME ON PROPERTIES OF COLLOIDAL SOLUTIONS OF SILICON NANOPARTICLES , pp. 6807, (2023)
   аннотация

   
   The design of semiconductor-metallic nanostructures using pulsed laser ablation in liquids (PLAL) is a very demanding task for biomedical applications being at an early stage of its development. Only few recent papers show the possibility of such a synthesis of composite nanoparticles as well as their perspectives for biosensing applications. However, mechanisms of the laser-stimulated formation of semiconductor-metallic nanoparticles involving several processes are not clarified yet being considerably depended on experimental conditions. In this work, we demonstrated an impact of the laser irradiation of colloidal solutions of silicon nanoparticles at different exposure time in the presence/absence of a gold target. In particular, longer ablation of the metal led to a stronger plasmonic maximum in silicon nanoparticles at around 520 nm. It also decreased the hydrodynamic size from 165 nm to 85 nm as well as the ξ-potential from –46 mV to –30 mV by increasing the ablation time from 0 s to 600 s. At the same time, the lowest electrical conductivity value (~1.5 μS/cm) of the plasmonic nanocomposites was detected at 120 s irradiation time. The highest concentration of synthesized composite nanoparticles (~3·1011 NPs/mL) was achieved at 180 s ablation time. Another purpose of the paper was to reveal an influence of the used laser irradiation on properties of the colloidal solutions of silicon nanoparticles themselves. It was found a considerable decrease of their absorbance with the increase of the laser exposure time that can be associated with the change of their properties (e.g. concentration, size, oxidation state etc.). Thus, the laser irradiation strongly affects properties of colloidal solutions of silicon nanoparticles that must also be taken into account considering possible mechanisms of the formation of composite nanostructures. Presented in the paper fast optical diagnostic can help to determine properties of colloidal solutions of nanocomposites formed by PLAL prior their biomedical or catalytic applications.
   
3. 
   Multi-Modal Laser-Fabricated Nanocomposites with Non-Invasive Tracking Modality and Tuned Plasmonic Properties , vol. 13, N9, pp. 1381, (2023)
   аннотация

   
   Ultrapure composite nanostructures combining semiconductor and metallic elements as a result of ultrafast laser processing are important materials for applications in fields where high chemical purity is a crucial point. Such nanocrystals have already demonstrated prospects in plasmonic biosensing by detecting different analytes like dyes and bacteria. However, the structure of the nanocomposites, as well as the control of their properties, are still very challenging due to the significant lack of research in this area. In this paper, the synthesis of silicon–gold nanoparticles was performed using various approaches such as the direct ablation of (i) a gold target immersed in a colloidal solution of silicon nanoparticles and (ii) a silicon wafer immersed in a colloidal solution of plasmonic nanoparticles. The formed nanostructures combine both plasmonic (gold) and paramagnetic (silicon) modalities observed by absorbance and electron paramagnetic resonance spectroscopies, respectively. A significant narrowing of the size distributions of both types of two-element nanocrystals as compared to single-element ones is shown to be independent of the laser fluence. The impact of the laser ablation time on the chemical stability and the concentration of nanoparticles influencing their both optical properties and electrical conductivity was studied. The obtained results are important from a fundamental point of view for a better understanding of the laser-assisted synthesis of semiconductor–metallic nanocomposites and control of their properties for further applications.
   
4. 
   Plasmon-affected luminescent nanothermometry with multi-band SiNPs/SiNX nanocomposites , vol. 260, pp. 119891, (2023)
   аннотация

   
   The design of luminescent multi-functional nanoplatforms that can be simultaneously employed for various applications is still an important research task nowadays. Nanosilicon is one of the most promising nanomaterial having unique structural and optoelectronic properties that can be used in biomedicine, optoelectronics, sensing and nanothermometry. However, its properties do not allow the creation of one luminescent multi-functional nanoplatform requiring merging of different nanomaterials. In this work, temperature-sensitive silicon-based nanocomposites with tuned multi-band emission are demonstrated. One can easily achieve the change of their single- and multi-band photoluminescence spectral position from ~1.6 eV to ~2.9 eV by varying the experimental parameters. Moreover, the “white” emission of silicon nitride is also observed that can be further applied for sensing or optoelectronic applications. Furthermore, the presence of silver nanoparticles leads to 80% increase of the temperature sensitivity of the photoluminescence maximum position (from ~540 μeV/◦ C to ~975 μeV/◦C). The plasmonic nanostructures also considerably modify the ratiometric temperature behavior of nanocomposite emission. The shown findings suggest perspectives of silicon-based nanostructures as multi-task luminescent nanoplatforms in the fields of nanothermometry, molecule sensing, optoelectronics and biomedicine.
   
5. 
   Laser-Assisted Nanosynthesis of Fluorescent Carbon Nanocomposites with Variable Plasmonic Properties , pp. 1-1, (2023)
   аннотация

   
   Laser-assisted material processing using ultrafast laser sources is an important and promising research direction aiming surface or volumetric modifications of different materials. In particular, pulsed laser ablation in liquids (PLALs) method allows forming a wide set of nanostructures in the form of colloidal solutions. Recently, this approach has also been demonstrated as an effective facile route of the successful formation of silicon-gold nanoparticles (Si-Au NPs) [1] that extended the application of silicon nanostructures in the field of plasmonics [2]. Nevertheless, the laser-assisted nanosynthesis of multi-element semiconductor-metallic nanoparticles is still challenging being at the initial stage of its development.
   
6. M Flimelová, YV Ryabchikov, NM Bulgakova, J Behrends
   A Facile Route of Manufacturing and Improvement of Plasmonic Nanostructures towards Magnetic Resonance Applications , pp. 68, (2023)
   аннотация

   
   Multicomponent nanostructures consisting of several elements have attracted a broad research interest being served for various aspects in the field of biosensing, catalysis, photovoltaics and biomedicine. Their synthesis by a pulsed laser ablation in a water enables eliminating various side effects originated from chemical contamination. Variable experimental conditions lead to tuning plasmonic and magnetic features influenced by physicochemical reactions during synthesis, thus enhancing their functionality. In this work, we performed synthesis of hybrid AuSi nanoparticles (NPs) with novel modalities by ultrashort laser ablation of bulk gold in water containing silicon NPs. The Au/Si atomic ratio in the nanohybrids was finely varied from 0.5 to 3.5 when changing the initial Si NPs concentration in water from 70 µg/mL to 10 µg/mL respectively. It has been found that the laser-fluence-insensitive silicon content depends on the mass of nanohybrids. A high concentration of paramagnetic defects (2.2 ꞏ1018 spin/g) in polycrystalline plasmonic NPs has been achieved. Our findings can open further prospects for plasmonic nanostructures as contrast agents in optical and magnetic resonance imaging techniques, biosensing and cancer theranostics.
   
7. M Flimelová, YV Ryabchikov, NM Bulgakova, J Behrends
   A Facile Route of Manufacturing and Improvement of Plasmonic Nanostructures towards Magnetic Resonance Applications , pp. 68, (2023)
   аннотация

   
   Multicomponent nanostructures consisting of several elements have attracted a broad research interest being served for various aspects in the field of biosensing, catalysis, photovoltaics and biomedicine. Their synthesis by a pulsed laser ablation in a water enables eliminating various side effects originated from chemical contamination. Variable experimental conditions lead to tuning plasmonic and magnetic features influenced by physicochemical reactions during synthesis, thus enhancing their functionality. In this work, we performed synthesis of hybrid AuSi nanoparticles (NPs) with novel modalities by ultrashort laser ablation of bulk gold in water containing silicon NPs. The Au/Si atomic ratio in the nanohybrids was finely varied from 0.5 to 3.5 when changing the initial Si NPs concentration in water from 70 µg/mL to 10 µg/mL respectively. It has been found that the laser-fluence-insensitive silicon content depends on the mass of nanohybrids. A high concentration of paramagnetic defects (2.2 ꞏ1018 spin/g) in polycrystalline plasmonic NPs has been achieved. Our findings can open further prospects for plasmonic nanostructures as contrast agents in optical and magnetic resonance imaging techniques, biosensing and cancer theranostics.
   

1. Miroslava Flimelova, Yury V Ryabchikov
   A Facile Route of Manufacturing of Silicon-Based Nanostructures with Tuned Plasmonic Properties , vol. 2015, N1, pp. 012128, (2021)
   аннотация

   
   An environment-friendly method of pulsed laser ablation in liquids is successfully employed for structural modification of silicon nanoparticles leading to a considerable narrowing of their size distribution accompanied with a reduction of the mean size. Contamination-free conditions of synthesis ensure the chemical purity of formed nanostructures that may reduce toxicity issues. Such a laser-induced modification leads to the appearance of plasmonic properties in semiconductor-based nanomaterials. Their spectral position can easily be varied in the whole visible range. Combined in one nanoparticle properties of semiconductors and noble metals can strongly promote applications of composite laser-synthesized nanoparticles for biosensing (using their plasmonic-based surface-enhanced ability) and bioimaging (using their both optical and magnetic abilities) purposes.
   
2. Miroslava Flimelova, Yury V Ryabchikov
   Laser Synthesis of Chemically Pure Multielement Metal-Based Nanostructures , vol. 21, pp. 73-73, (2021)
   аннотация

   
   Multicomponent nanostructures consisting of several elements reveal a large research interest being served for various aspects in the field of biomedicine [1, 2]. Combining different elements in a nanoparticle one can easily vary their physicochemical properties in a wide range adjusting their functionality. However, using chemical-based methods for synthesis can considerably obstruct their applications in biomedical fields due to their contamination by chemical residuals. To overcome the aforementioned issues a versatile method of pulsed laser ablation in liquids is widely employed for the synthesis of pure one-and bi-metallic nanostructures widening their functional properties. As a result, they show wide prospects for applications in various fields of biomedicine, eg as contrast agents for magnetic resonance imaging [3, 4]. However, manufacturing of composite metallic-based nanoparticles doped with semiconductor elements by means of pulsed laser ablation method is still challenging being at the early stage of its development. Nevertheless, laser-synthesized metallic-semiconductor nanocomposites have already shown promising perspectives for molecule detection using surface-enhanced Raman scattering (SERS) or infrared absorption techniques (SEIRA) having tracking features as Raman modality or paramagnetic defect labels at the same time [5, 6]. In this work, gold-silicon nanocomposites with dual modalities were fabricated by direct femtosecond laser ablation in deionized water and characterized by structural and optical techniques. A method of chemical content variation is developed allowing fine-tuning of ratio between gold and …
   

1. Yury V Ryabchikov, Jan Behrends
   Expedient paramagnetic properties of surfactant-free plasmonic silicon-based nanoparticles , vol. 52, N3, pp. 177, (2020)
   аннотация

   
   Surfactant-free multifunctional semiconductor-metallic nanostructures possessing several modalities are formed due to laser-induced structural modification of pure silicon nanoparticles in the presence of gold. It results to variable size-dependent chemical composition examined by energy-dispersive X-ray spectroscopy. Laser-synthesized silicon-based nanocomposites exhibit remarkable both plasmonic and paramagnetic properties. Their plasmonic maxima are found to be easily adjusted in the whole visible spectral range. Influence of resonant laser irradiation on spin behaviour of silicon-gold nanoparticles is established. Their spin–lattice and spin–spin relaxation processes are investigated as well. Such multifunctional nanoparticles can reveal a huge potential for different applications in field of nanomedicine, in particular, for biosensing and bioimaging.
   

1. 
   Facile laser synthesis of multimodal composite silicon/gold nanoparticles with variable chemical composition , vol. 21, N4, pp. 85, (2019)
   аннотация

   
   Multimodal contamination-free composite silicon/gold nanoparticles are synthesized by “green” laser ablation approach. Their concentration-dependent size distribution and chemical composition are studied by means of transmission electron microscopy coupled with energy-dispersive X-ray spectroscopy. The influence of applied laser fluence on both size distribution and chemical composition is also investigated. The size-dependent chemical composition of formed nanocomposites is analyzed. Optoelectronic properties of silicon/gold nanoparticles as well as their ability to molecule detection using surface-enhanced Raman scattering are studied as well.
   
2. A Yu Kharin, VV Lysenko, A Rogov, Yu V Ryabchikov, A Geloen, I Tishchenko, O Marty, PG Sennikov, RA Kornev, IN Zavestovskaya, V Kabashin, V Yu Timoshenko
   Nonlinear optical responses of SI nanocrystals for bioimaging technologies , pp. 36-37, (2019)
3. 
   UNIQUE APPLICATIONS OF OPTICAL PROPERTIES OF SILICON NANOSTRUCTURES , pp. 3573, (2019)
   аннотация

   
   Silicon nanostructures can be prepared by different methods that considerably change their optical properties depending on experimental conditions. They are also very sensitive to molecular environment and external influences that can be used for multiple applications in different areas. Silicon nanostructures prepared by laser ablation show large perspectives for molecular sensing and biomedical applications. In this paper, an overview of optical properties of silicon nanostructures with focus on nanoparticles prepared by ultrafast laser ablation in liquids is provided. It is shown that they reveal wide prospects for applications in nanobiomedicine and their unique characteristics can be significantly enhanced due to laser-induced metal incorporation. Metal inclusions lead to appearance of plasmonic properties in semiconductor nanomaterials that can be applied for molecule detection using surface enhancing of optical response.
   
4. Yury V Ryabchikov, Anatolii Lukianov, Bohdan Oliinyk, Tetyana Nychyporouk, Vladimir Lysenko
   Development of silicon nitride-based nanocomposites with multicolour photoluminescence Applied Physics A., vol. 125, pp. 1-7, (2019)
   аннотация

   
   Silicon-rich nitride nanocomposites with stable multicolour photoluminescence (PL) are developed in this work. Firstly, a single PL band can be adjusted in the visible spectral range. Secondly, simultaneous emission of an additional PL band is achieved due to boron-doping of the nanocomposites. Impact of thermal annealing of the silicon nitride films in different atmospheres at various temperatures on their PL spectra is studied. Processes responsible for multicolour emission in the boron-doped nanocomposites are discussed. The developed nanocomposites can be further applied for nanothermometry or biosensing applications. They can be also used for synthesis of silicon nanoparticles with multicolour PL.
   
5. Alexander Yu Kharin, Vladimir V Lysenko, Andrei Rogov, Yuri V Ryabchikov, Alain Geloen, Igor Tishchenko, Olivier Marty, Peter G Sennikov, Roman A Kornev, Irina N Zavestovskaya, Andrei V Kabashin, Victor Yu Timoshenko
   Bi‐modal nonlinear optical contrast from si nanoparticles for cancer theranostics , vol. 7, N13, pp. 1801728, (2019)
   аннотация

   
   Presenting a safe alternative to conventional compound quantum dots and other functional nanostructures, nanosilicon can offer a series of breakthrough hyperthermia-based therapies under near-infrared, radiofrequency, ultrasound, etc., excitation, but the size range to sensitize these therapies is typically too large (>10 nm) to enable efficient imaging functionality based on photoluminescence properties of quantum-confined excitonic states. Here, it is shown that large Si nanoparticles (NPs) are capable of providing two-photon excited luminescence (TPEL) and second harmonic generation (SHG) responses, much exceeding that of smaller Si NPs, which promises their use as probes for bi-modal nonlinear optical bioimaging. It is finally demonstrated that the combination of TPEL and SHG channels makes possible efficient tracing of both separated Si NPs and their aggregations in different cell compartments, while the resolution of such an approach is enough to obtain 3D images. The obtained bi-modal contrast provides lacking imaging functionality for large Si NPs and promises the development of novel cancer theranostic modalities on their basis.
   
6. Sanna Uusitalo, Martin Kögler, Alexey Popov, Yury Ryabchikov, Olga Bibikova, Hanna-Leena Alakomi, Riikka Juvonen, Ville Kontturi, Samuli Siitonen, Anna-Liisa Välimaa, Riitta Laitinen, Anton Popov, Gleb Tselikov, Ahmed Al-Kattan, Peter Neubauer, Andrei V K
   Surface-enhanced Raman spectroscopy for beverage spoilage yeasts and bacteria detection with patterned substrates and gold nanoparticles (Conference Presentation) , vol. 10907, pp. 1090703, (2019)
   аннотация

   
   In food industry, detection of spoilage yeasts such as W. anomalus and B. bruxellensis and pathogens such as certain Listeria and E. coli species can be laborious and time-consuming. In the present study, a simple and repeatable technique was developed for rapid yeast detection using a combination of patterned gold coated polymer SERS substrates and gold nanoparticles [1−4]. For the first time, a state-of-the-art time-gated Raman detection approach was used as a complementary technique to show the possibility of using 532-nm pulsed laser excitation and avoid the destructive influence of induced fluorescence [3]. Conventional nanoparticles synthesized by colloidal chemistry are typically contaminated by non-biocompatible by-products (surfactants, anions), which can have negative impacts on many live objects under examination (cells, bacteria) and thus decrease the precision of bioidentification.
   
7. 
   Laser-induced engineering and characterization of multimodal silicon-based nanoparticles , vol. 19, pp. 143-144, (2019)
   аннотация

   
   Recent progress in laser technologies provokes comprehensive studies on laser-matter interaction using various materials. One of the most interesting and most important employment of lasers is related to synthesis of new nanomaterials with unique properties for a wide set of applications. Interaction between ultrafast laser radiation and bulk/powder materials in different environments provokes efficient substance removal resulting to formation of nanoparticles with properties depending on experimental conditions [1]. Moreover, it has been shown lately that ultrafast laser irradiation significantly modifies semiconductor nanostructures in the presence of metal forming composite nanoparticles [2, 3]. Such a modification reveals unique modalities ensuring biomedical applications of nanocomposites, in particular, molecule detection by means of surface-enhanced Raman scattering [4]. Nevertheless, study of laser-synthesized composite nanostructures is at an early stage and information about their properties and applications as well is still missed in literature.
   
8. 
   Size Modification of Optically Active Contamination‐Free Silicon Nanoparticles with Paramagnetic Defects by Their Fast Synthesis and Dissolution Physica Status Solidi С, vol. 216, N2, pp. 1800685, (2019)
   аннотация

   
   Contamination‐free silicon‐based nanoparticles (NPs) with several modalities are developed in this work. They are formed by non‐toxic laser‐assisted decomposition of silicon microgranules homogeneously dispersed in deionized water. Precise control of numerous experimental parameters allows repeatable fine tuning of nanoparticle size solving significant lacks of a direct laser ablation routine. Such a method provokes a huge amount of paramagnetic defect states of optically active silicon NPs that can serve as a contrast agent for magnetic resonance and nonlinear optical imaging. Perspectives of their bioapplication are driven by detected their fast size degradation in a NaCl‐based medium.
   

1. 
   Bare laser-synthesized Au-based nanoparticles as nondisturbing surface-enhanced Raman scattering probes for bacteria identification , (2018)
   аннотация

   
   The ability of noble metal-based nanoparticles (NPs) (Au, Ag) to drastically enhance Raman scattering from molecules placed near metal surface, termed as surface-enhanced Raman scattering (SERS), is widely used for identification of trace amounts of biological materials in biomedical, food safety and security applications. However, conventional NPs synthesized by colloidal chemistry are typically contaminated by nonbiocompatible by-products (surfactants, anions), which can have negative impacts on many live objects under examination (cells, bacteria) and thus decrease the precision of bioidentification. In this article, we explore novel ultrapure laser-synthesized Au-based nanomaterials, including Au NPs and AuSi hybrid nanostructures, as mobile SERS probes in tasks of bacteria detection. We show that these Au-based nanomaterials can efficiently enhance Raman signals from model R6G molecules, while the enhancement factor depends on the content of Au in NP composition. Profiting from the observed enhancement and purity of laser-synthesized nanomaterials, we demonstrate successful identification of 2 types of bacteria (Listeria innocua and Escherichia coli). The obtained results promise less disturbing studies of biological systems based on good biocompatibility of contamination-free laser-synthesized nanomaterials.
   
2. 
   Recent Advances in Laser-Ablative Synthesis of Bare Au and Si Nanoparticles and Assessment of Their Prospects for Tissue Engineering Applications , (2018)
   аннотация

   
   Driven by surface cleanness and unique physical, optical and chemical properties, bare (ligand-free) laser-synthesized nanoparticles (NPs) are now in the focus of interest as promising materials for the development of advanced biomedical platforms related to biosensing, bioimaging and therapeutic drug delivery. We recently achieved significant progress in the synthesis of bare gold (Au) and silicon (Si) NPs and their testing in biomedical tasks, including cancer imaging and therapy, biofuel cells, etc. We also showed that these nanomaterials can be excellent candidates for tissue engineering applications. This review is aimed at the description of our recent progress in laser synthesis of bare Si and Au NPs and their testing as functional modules (additives) in innovative scaffold platforms intended for tissue engineering tasks.
   
3. И.А. Белогорохов, Л.И. Белогорохова, В.Е. Пушкарев
   Люминесцентные свойства композитных систем на основе поЛистироЛа и фтаЛоцианинатов эрбиЯ(III) в бЛижней ик обЛасти , (2018)
   аннотация

   
   Получены композитные материалы на основе полистирола и фталоцианинатов ErIII одно-, двух- и трёхпалубного строения, изучены их спектральные люминесцентные характеристики в ближнем ИК (БИК) диапазоне. Для всех исследованных комплексов в составе композитов характерна 4f фотолюминесценция (ФЛ), которая в случае моно- и трис(фталоцианината) наблюдается при 1550 нм, в случае же бис(фталоцианината) максимум ФЛ смещён в коротковолновую область и проявляется при 1440 нм. Проведен сравнительный анализ свойств композитов и индивидуальных фталоцианиновых соединений в пленках и растворе. Так, например, в случае однопалубного фталоцианина данную эмиссию удалось зафиксировать впервые именно в матрице полистирола – для индивидуальных моно(фталоцианинатов) ErIII этот процесс ранее не наблюдался.
   
4. A Danilov, G Tselikov, AV Kabashin, F Wu, VG Kravets, AN Grigorenko, I Ozerov, F Bedu, AA Popov, A Al-Kattan, GI Tselikov, YV Ryabchikov, VP Nirwan, A Fahmi, E Munnier, I Chourpa
   Том. 10521. Synthesis and Photonics of Nanoscale Materials XV.-Сер. Synthesis and Photonics of Nanoscale Materials XV , (2018)
5. Anton A Popov, Ahmed Al-Kattan, Viraj P Nirwan, Emilie Munnier, Gleb I Tselikov, Yury V Ryabchikov, Igor Chourpa, Amir Fahmi, AV Kabashin
   Bare laser-synthesized Si nanoparticles as functional elements for chitosan nanofiber-based tissue engineering platforms , vol. 10521, pp. 10-17, (2018)
   аннотация

   
   Methods of femtosecond laser ablation were used to fabricate bare (ligand-free) silicon (Si) nanoparticles in deionized water. The nanoparticles were round in shape, crystalline, free of any impurities, and water-dissolvable, while the dissolution rate depended on the concentration of oxygen defects in their composition. The nanoparticles were then eletrospun with chitosan to form nanoparticle decorated nanofibrous matrices. We found that the functionalization of nanofibers by the nanoparticles can affect the morphology and physico-chemical characteristics of resulting nanostructures. In particular, the presence of Si nanoparticles led to the reduction of fibers thickness, suggesting a potential improvement of fiber’s surface reactivity. We also observed the improvement of thermal stability of hybrid nanofibers. We believe that the incorporated Si nanoparticles can serve as functional elements to improve characteristics …
   

1. 
   Surface enhanced infrared absorption spectroscopy based on gold nanostars and spherical nanoparticles , (2017)
   аннотация

   
   Plasmonic anisotropic nanoparticles possess a number of hot spots on their surface due to the presence of sharp edges, tips or vertices, leading to a high electric field strength surrounding the nanostructures. In this paper, we explore different plasmonic nanostructures, including anisotropic gold nanostars (AuNSts) and spherical gold nanoparticles, in surface-enhanced infrared absorption spectroscopy (SEIRAS) in an attenuated total reflection (ATR) configuration. In our experiments, we observed up to 10-times enhancement of the infrared (IR) absorption of thioglycolic acid (TGA) and up to 2-times enhancement of signals for bovine serum albumin (BSA) protein on plasmonic nanostructure-based films deposited on a silicon (Si) internal reflection element (IRE) compared to bare Si IRE. The dependence of the observed enhancement on the amount of AuNSts present at the surface of the IRE has been demonstrated. Quantitative studies with both, TGA and BSA were performed, observing that the SEIRA signal can be correlated to the concentration of analyte molecules present within the evanescent field. The calibration curves in the presence of the AuNSts showed enhanced sensitivity as compared with the bare Si IRE.We finally compare efficiencies of anisotropic AuNSts and spherical citrate-capped and “bare” laser-synthesized gold nanoparticles as SEIRAS substrates for the detection of TGA and BSA. The signal obtained from AuNSts was at least 2 times higher for TGA molecules in comparison with spherical gold nanoparticles, which was explained by a more efficient generation of hot spots on anisotropic surface due to the presence of sharp edges, tips or vertices, leading to a high electric field strength surrounding the AuNSts.
   
2. 
   Influence of oxidation state on water solubility of Si nanoparticles prepared by laser ablation in water , (2017)
   аннотация

   
   Femtosecond laser fragmentation from preliminarily prepared water-dispersed Si microcolloids was used to synthesize bare (ligand-free) spherical silicon nanoparticles (Si-NPs) with low size dispersion and controllable mean size from a few nm to several tens of nm. In order to control the oxidation state of Si-NPs, the fragmentation was performed in normal oxygen-saturated water (oxygen-rich conditions) or in water disoxygenated by pumping with noble gases (Ag, He) before and during the experiment (oxygen-free conditions). XPS and TEM studies revealed that Si-NPs were composed of Si nanocrystals with inclusions of silicon oxide species, covered by SiOx (1 x 2) shell, while the total oxide content depended whether Si-NPs were prepared in oxygen-rich or oxygen-free conditions. When placed into a dialysis box, waterdispersed Si-NPs rapidly dissolved, which was evidenced by TEM data. In this case, NPs prepared under oxygen-rich conditions demonstrated much faster dissolution kinetics and their complete disappearance after 7-10 days, while the dissolution process of less oxidized counterparts could last much longer (25-30 days). Much fast dissolution kinetics of more oxidized Si-NPs was attributed to more friable structure of nanoparticle core due to the presence of numerous oxidation-induced defects. Laser-synthesized Si-NPs are of paramount importance for biomedical applications.
   
3. 
   Surface-enhanced Raman spectroscopy for identification and discrimination of beverage spoilage yeasts using patterned substrates and gold nanoparticles , (2017)
   аннотация

   
   In the beverage industry, the detection of spoilage yeasts such as Wickerhamomyces anomalus and Brettanomyces bruxellensis can be labourious and time-consuming. In the present study, a simple and repeatable technique was developed for rapid yeast detection using a combination of patterned goldcoated surface-enhanced Raman spectroscopy (SERS) substrates and gold nanoparticles. W. anomalus and B. bruxellensis showed several characteristic peaks, enabling the discrimination of these yeasts without chemometric analysis. The control yeast used as an indicator yeast, Rhodotorula mucilaginosa, showed 7 cell wall-related peaks originating from lipids and haemoproteins. AnalysingW. anomalus SERS spectra with differently sized and shaped gold nanoparticles revealed the benefit of using either large, spherical, chemically synthesised gold nanoparticles or small, laser-synthesised, gold-silicon nanoparticles for yeast detection. Additionally, the spectra showed differences in SERS signal construction for small molecules and biological cells, as the nanoparticles with best response in biological cell detection did not excel in small molecule detection. The use of small composite gold-silicon nanoparticles in combination with the SERS substrate gave distinctive spectra for all detected yeast species.
   
4. 
   Cavitation-Free Continuous-Wave Laser Ablation from a Solid Target to Synthesize Low-Size-Dispersed Gold Nanoparticles , (2017)
   аннотация

   
   Continuous wave (CW) radiation from a Yb-fiber laser (central wavelength 1064 nm, power 1–200 W) was used to initiate ablation of a gold target in deionized water and to synthesize bare (unprotected) gold nanoparticles. We show that the formed nanoparticles present a single low-size-dispersed population with a mean size of the order of 10 nm, which contrasts with previously reported data on dual populations of nanoparticles formed during pulsed laser ablation in liquids. The lack of a second population of nanoparticles is explained by the absence of cavitation-related mechanism of material ablation, which typically takes place under pulsed laser action on a solid target in liquid ambience, and this supposition is confirmed by plume visualization tests. We also observe a gradual growth of mean nanoparticle size from 8–10 nm to 20–25 nm under the increase of laser power for 532 nm pumping wavelength, whereas for 1064 nm pumping wavelength the mean size 8– 10 nm is independent of radiation power. The growth of the nanoparticles observed for 532 nm wavelength is attributed to the enhanced target melting and splashing followed by additional heating due to an efficient excitation of plasmons over gold nanoparticles. Bare, low-size-dispersed gold nanoparticles are of importance for a variety of applications, including biomedicine, catalysis, and photovoltaics. The use of CW radiation for nanomaterial production promises to improve the cost efficiency of this technology.
   

1. 
   Nonlinear Optical Properties of Silicon Carbide (SiC) Nanoparticles by Carbothermal Reduction , (2016)
   аннотация

   
   SiC nanoparticles by carbothermal reduction show promising properties in terms of second harmonic and multiphoton excited luminescence. In particular, we estimate a nonlinear eciency = 17 pm/V, as obtained by Hyper Rayleigh Scattering. We also present results of cell labelling to demonstrate the potential use of SiC nanoparticles for nonlinear bioimaging by simultaneous detection of second harmonic and luminescence.
   
2. 
   Ultrapure laser-synthesized Sibased nanomaterials for biomedical applications: in vivo assessment of safety and biodistribution , (2016)
   аннотация

   
   Si/SiOx nanoparticles (NPs) produced by laser ablation in deionized water or aqueous biocompatible solutions present a novel extremely promising object for biomedical applications, but the interaction of these NPs with biological systems has not yet been systematically examined. Here, we present the first comprehensive study of biodistribution, biodegradability and toxicity of laser-synthesized Si-SiOx nanoparticles using a small animal model. Despite a relatively high dose of Si-NPs (20 mg/kg) administered intravenously in mice, all controlled parameters (serum, enzymatic, histological etc.) were found to be within safe limits 3 h, 24 h, 48 h and 7 days after the administration. We also determined that the nanoparticles are rapidly sequestered by the liver and spleen, then further biodegraded and directly eliminated in urine without any toxicity effects. Finally, we found that intracellular accumulation of Si-NPs does not induce any oxidative stress damage. Our results evidence a huge potential in using these safe and biodegradable NPs in biomedical applications, in particular as vectors, contrast agents and sensitizers in cancer therapy and diagnostics (theranostics).
   
3. 
   Ultrapure laser-synthesized Si nanoparticles with variable oxidation states for biomedical applications , (2016)
   аннотация

   
   We employ a method of femtosecond laser fragmentation of preliminarily prepared water-dispersed microcolloids to fabricate aqueous solutions of ultrapure bare Si-based nanoparticles (Si-NPs) and assess their potential for biomedical applications. The nanoparticles appear spherical in shape, with low size dispersion and a controllable mean size, from a few nm to several tens of nm, while a negative surface charge (35 mV  0.10 according to z-potential data) provides good electrostatic stabilization of colloidal Si-NP solutions. Structural analysis shows that the Si-NPs are composed of Si nanocrystals with inclusions of silicon oxide species, covered by a SiOx (1 o x o 2) shell, while the total oxide content depends on whether the fragmentation is performed in normal oxygen-saturated water (oxygen-rich conditions) or in water deoxygenated by pumping with noble gases (Ag or He) before and during the experiment (oxygen-free conditions). Our dissolution tests show the excellent water-solubility of all the NPs, while more oxidized NPs demonstrate much faster dissolution kinetics, which is explained by oxidation-induced defects in the core of the Si-NPs. Finally, by examining the interaction of the NPs with human cells after 72 h of incubation at different concentrations, we report the absence of any adverse effects of the NPs up to high concentrations (50 mg mL1) and a good internalization of NPs via a classical endocytosis mechanism. Possessing far superior purity compared to their chemically synthesized counterparts and enabling a variety of imaging and therapeutic functionalities, the laser-synthesized Si-NPs are promising for safe and efficient applications in nanomedicine.
   
4. 
   Si nanoparticles as sensitizers for radio frequency-induced cancer hyperthermia , (2016)
   аннотация

   
   We review our recently obtained data on the employment of Si nanoparticles as sensitizers of radiofrequency (RF) - induced hyperthermia for mild cancer therapy tasks. Such an approach makes possible the heating of aqueous suspensions of Si nanoparticles by tens of degrees Celsius under relatively low intensities (1–5 W/cm2) of 27 MHz RF radiation. The heating effect is demonstrated for nanoparticles synthesized by laser ablation in water and mechanical grinding of porous silicon, while laser-ablated nanoparticles demonstrate a remarkably higher heating rate than porous silicon-based ones for the whole range of the used concentrations. The observed RF heating effect can be explained in the frame of a model considering the polarization of Si NPs and electrolyte in the external oscillating electromagnetic field and the corresponding release of heat by electric currents around the nanoparticles. Our tests evidence relative safety of Si nanostructures and their efficient dissolution in physiological solutions, suggesting potential clearance of nanoparticles from a living organism without any side effects. Profiting from Si nanoparticle-based heating, we finally demonstrate an efficient treatment of Lewis Lung carcinoma in vivo. The obtained data promise a breakthrough in the development of mild, non-invasive methods for cancer therapy.
   
5. 
   Structural properties of gold-silicon nanohybrids formed by femtosecond laser ablation in water at different fluences , (2016)
   аннотация

   
   A gold target was ablated by femtosecond laser radiation in aqueous solutions of preliminarily prepared Si nanoparticles. The ablation process led to the formation of Au-based spherical colloids with the mean size around 5-10 nm and a weak abundance of larger species. Transmission Electron Microscopy (TEM) and Energy Dispersive X-ray (EDX) analysis revealed the presence of Au and Si in colloid composition, while the stoichiometry of colloids did not depend on laser fluence during the fabrication experiments. The formation of Au-Si nanohybrid structure was explained by an effect of the interaction of laser-ablated Au nanoclusters with water-dispersed Si nanoparticles. The fabricated structures can be of importance for biomedical, catalysis, and photovoltaics applications.
   
6. 
   Laser ablative nanostructuring of Au in liquid ambience in continuous wave illumination regime , (2016)
   аннотация

   
   We study surface modifications and fabrication of nanoparticles under ablation of water-immerged Au target by a moving beam of continuous wave Ytterbium fiber laser (532, 1064 nm). Our analysis of the target surface reveals the presence of solidified nanoscale Au nanoparticles distributed over the crater of the laser beam, which is consistent with the presence of metal melting and evaporation effects. Optical imaging of the hydrodynamic process shows the presence of convective flows leading to a strong mixing of the liquid medium during the laser ablation process. The laser ablation process results in the production of gold nanoparticle colloids with average particle sizes smaller than 10 nm under relatively narrow size dispersion. Au nanoparticles prepared by CW laser ablation of Au in deionized water are of importance for a variety of applications, including biomedical, catalysis and electrocatalysis, photovoltaics etc.
   
7. 
   Detection of Listeria innocua on roll-to-roll produced SERS substrates with gold nanoparticles , (2016)
   аннотация

   
   The rapid and accurate detection of food pathogens plays a critical role in the early prevention of foodborne epidemics. Current bacteria identification practices, including colony counting, polymerase chain reaction (PCR) and immunological methods, are time consuming and labour intensive; they are not ideal for achieving the required immediate diagnosis. Different SERS substrates have been studied for the detection of foodborne microbes. The majority of the approaches are either based on costly patterning techniques on silicon or glass wafers or on methods which have not been tested in large scale fabrication. We demonstrate the feasibility of analyte specific sensing using mass-produced, polymerbased low-cost SERS substrate in analysing the chosen model microbe with biological recognition. The use of this novel roll-to-roll fabricated SERS substrate was combined with optimised gold nanoparticles to increase the detection sensitivity. Distinctive SERS spectral bands were recorded for Listeria innocua ATCC 33090 using an in-house build (785 nm) near infra red (NIR) Raman system. Results were compared to both those found in the literature and the results obtained from a commercial time-gated Raman system with a 532 nm wavelength laser excitation. The effect of the SERS enhancer metal and the excitation wavelength on the detected spectra was found to be negligible. The hypothesis that disagreements within the literature regarding bacterial spectra results from conditions present during the detection process has not been supported. The sensitivity of our SERS detection was improved through optimization of the concentration of the sample inside the hydrophobic polydimethylsiloxane (PDMS) wells. Immunomagnetic separation (IMS) beads were used to assist the accumulation of bacteria into the path of the beam of the excitation laser. With this combination we have detected Listeria with gold enhanced SERS in a label free manner from such low sample concentrations as 104 CFU ml
   1.
   

1. 
   Enhanced Thermal Sensitivity of Silicon Nanoparticles Embedded in (Nano-Ag/)SiNx for Luminescent Thermometry , (2014)
   аннотация

   
   Steady-state photoluminescence of silicon nanoparticles embedded in solid-state (nano-Ag/)SiNx thin films at above room temperature is studied and compared to silicon nanoparticles dispersed in low-polar liquids. Roles of local surface plasmons as well as general mechanisms responsible for the temperature-dependent photoluminescence are pointed out. Thermal sensitivities of photoluminescence spectral shape, maximum position, and full width at halfmaximum are estimated and application of the (nano-Ag/)SiNx layers as photoluminescent thermal screens is proposed.
   
2. 
   Radio frequency radiation-induced hyperthermia using Si nanoparticle-based sensitizers for mild cancer therapy , (2014)
   аннотация

   
   Offering mild, non-invasive and deep cancer therapy modality, radio frequency (RF) radiation-induced hyperthermia lacks for efficient biodegradable RF sensitizers to selectively target cancer cells and thus avoid side effects. Here, we assess crystalline silicon (Si) based nanomaterials as sensitizers for the RF-induced therapy. Using nanoparticles produced by mechanical grinding of porous silicon and ultraclean laser-ablative synthesis, we report efficient RF-induced heating of aqueous suspensions of the nanoparticles to temperatures above 45-506C under relatively low nanoparticle concentrations (,1 mg/mL) and RF radiation intensities (1–5 W/cm2). For both types of nanoparticles the heating rate was linearly dependent on nanoparticle concentration, while laser-ablated nanoparticles demonstrated a remarkably higher heating rate than porous silicon-based ones for the whole range of the used concentrations from 0.01 to 0.4 mg/mL. The observed effect is explained by the Joule heating due to the generation of electrical currents at the nanoparticle/water interface. Profiting from the nanoparticle-based hyperthermia, we demonstrate an efficient treatment of Lewis lung carcinomain vivo. Combined with the possibility of involvement of parallel imaging and treatment channels based on unique optical properties of Si-based nanomaterials, the proposed method promises a new landmark in the development of new modalities for mild cancer therapy.
   

1. 
   Photoluminescence thermometry with alkyl-terminated silicon nanoparticles dispersed in low-polar liquids , (2013)
   аннотация

   
   Steady-state and time-resolved photoluminescence of silicon nanoparticles dispersed in low-polar liquids at above room temperature is studied. The roles of low-polar liquids as well as mechanisms responsible for their temperature-dependent photoluminescence are discussed. The thermal sensitivity of the photoluminescence is estimated and application of the nanoparticles as nanothermometers is proposed.
   
2. 
   Design of microporous mixed zinc–nickel triazolate metal–organic frameworks with functional ligands , (2013)
   аннотация

   
   We report two new microporous mixed-metal triazolate based MOFs made from zinc and nickel salts combined with either 1,2,4-triazole or 3,5-diamino-1,2,4-triazole. Their structures, refined from X-ray powder diffraction, their CO2 adsorption and photoluminescent properties show a direct correlation with the structure of their parent organic ligand.
   
3. 
   Photoluminescence of silicon nanoparticles chemically modified by alkyl groups and dispersed in low-polar liquids , (2013)
   аннотация

   
   A detailed comparative analysis of photoluminescence behavior of silicon nanoparticles in air and dispersed in low-polar liquids is reported. Efficient dispersion and excellent stability of the chemically modified nanoparticles in low-polar liquids are achieved. Influence of the chemical functionalization and of the low-polar liquids on steady-state and timeresolved photoluminescence of the silicon nanoparticles is investigated. Role of low-polar liquids on recombination mechanisms taking place in the nanoparticles is discussed in terms of Fo¨rster resonant energy transfer processes. Effect of exciting laser power on photoluminescence spectra of the silicon nanoparticles both in air and in low-polar liquids is investigated and the electronic mechanisms involved into the observed phenomena are discussed.
   

1. 
   Luminescence behavior of silicon and carbon nanoparticles dispersed in low-polar liquids , (2012)
   аннотация

   
   A comparative photoluminescence analysis of as-prepared and chemically modified (by alkyl chains -C18H37) silicon and carbon nanoparticles dispersed in low-polar liquids is reported. Influence of the low-polar liquid nature and ambient temperature on photoluminescence of the nanoparticles has been investigated from the point of view of their possible application as thermal nanoprobes.
   
2. 
   Transport and Spectroscopic Features of Composite Semiconductor Material Based on Poly[2-Methoxy-5- (2-Ethyl-Hexyloxy)-1,4-Phenylene-Vinylene] , (2012)
   аннотация

   
   For the first time we report on investigations of the electrical transport properties of multicomponent polymer systems based on [2-methoxy-5-(2-etilgeksiloksi)-1,4-phenylene vinylene-] (MEH-PPV) molecules. The temperature dependences of dark conductivity on DC allow us to find a polaron mechanism of the charge transport with activation energy of 0.058 eV, which can be explained by an influence of phthalocyanine complex embedded in a polymer matrix as nanoimpurity. Theoretical calculations with Molecular Mechanics Universal Force Field (UFF) reveal that a set of Pc molecules has the dipole moment of 1.1276 Debye and its direction is from nitrogen atoms in the center of Pc ring to benzene groups in the periphery of the Pc molecule. Infrared optical spectroscopy data demonstrate that incorporation of the phthalocyanine complexes into the polymeric matrix leads to appearance of a set of the absorption lines in the region of 750÷3340 cm−1.
   
3. 
   Vibronic States in Organic Semiconductors Based on NonMetal Naphthalocyanine. Detection of Heterocyclic Phthalocyanine Compounds in a Flexible Dielectric Matrix , (2012)
   аннотация

   
   The vibronic properties of semiconductor structures based on nonmetal naphthalocyanine molecules are studied using IR and Raman spectroscopy methods. New absorption lines in the transmission spectra of such materials are detected and identified. Three transmission lines are observed in the range 2830– 3028 cm–1, which characterize carbon–hydrogen bonds of peripheral molecular groups. Their spectral positions are 2959, 2906, and 2866 cm–1. It is detected that the phthalocyanine ring can also exhibit its specific vibronic properties in the Raman spectra at 767, 717, and 679 cm–1. The naphthalocyanine molecule in the organic dielectric matrix of microfibers is described using IR spectroscopy. It is shown that the set of vibrations characterizing the isoindol group, pyrrole ring, naphtha group, and C–H bonds, allows an accurate enough description of the vibronic states of the naphthalocyanine complex in complex heterostructures to be made. The spectral range with fundamental modes, characterizing a naphthalocyanine semiconductor in a heterostructure, is 600–1600 cm–1. A comparison of the compositions of complex systems with a similar heterostructure containing lutetium diphthalocyanine demonstrated few errors.
   

1. 
   Features of the Spectral Dependences of Transmittance of Organic Semiconductors Based on TertButyl Substituted Lutetium Phthalocyanine Molecules , (2011)
   аннотация

   
   Vibronic properties of organic semiconductors based on tertabutyl substituted phthalocyanine lutetium diphthalocyanine molecules are studied by IR and Raman spectroscopy. It is shown that substitution of several carbon atoms in initial phthalocyanine (Pc) ligands with 13C isotope atoms causes a spectral shift in the main absorption lines attributed to benzene, isoindol, and peripheral C–H groups. A comparison of spectral characteristics showed that the shift can vary from 3 to 1 cm–1.
   
2. 
   Infrared Spectroscopy of Semiconductor Structures Based on Alkyl-Substituted Lanthanide (III) Clam-Shell Mono-, Di-, and Di-Trisphthalocyanine Complexes , (2011)
   аннотация

   
   Optical properties of semiconductor structures based on clam-shell phthalocyanine complexes have been studied by Fourier Transform Infrared Spectrometry. Transmission spectra of metal-free monophthalocyanine, bis-phthalocyanine of Eu and Eu di-tris-phthalocyanine organic semiconductors were have been obtained and analyzed. Comparison of spectral data from different clam-shell complexes revealed that magnetic f–f interaction of Eu atoms increase the energy of vibronic states which is clearly indicated by the spectral shift of absorption lines position. A new set of absorption lines in the 2360÷2341 cm−1 range was observed. It was suggested that these lines correspond to vibrations of orto-bis(oximetil)phenol group. It was found that vibronic modes of the phtalocyanine-ring reveal several absorption lines with spectral coordinates 526 cm−1, 502 cm−1, 484 cm−1, 467 cm−1 in the far infrared region.
   
3. 
   Photosensitized Generation of Singlet Oxygen in Powders and Aqueous Suspensions of Silicon Nanocrystals , (2011)
   аннотация

   
   The photoluminescence spectra and kinetics in powders and aqueous suspensions produced from porous silicon layers are studied. The systematic features of photosensitized generation of singlet oxygen by silicon nanocrystals in the samples are established. The dependence of the efficiency of generation of singlet oxygen on the pressure of molecular oxygen is analyzed. It is concluded that the generation can be described on the basis of concepts of energy transfer from photoexcited silicon nanocrystals to oxygen molecules adsorbed at the nanocrystal surface to the concentration described by Langmuir’s adsorption model. The processes limiting the efficiency of photosensitized generation of singlet oxygen in the systems are discussed.
   
4. 
   Study of the Transport Properties of Organic Semiconductors Based on Europium Diphthalocyanine and bitrisPhthalocyanine Complexes with orthobis(Oxymethyl)Phenyl Bridge and Based on Erbium and Europium Dinaphthalocyanine Complexes , (2011)
   аннотация

   
   The transport properties of organic semiconductors based on europium diphthalocyanine and bi-tris-phthalocyanine complexes with ortho-bis(oxymethyl)phenyl bridge and based on europium and erbium dinaphthalocyanine are studied. The temperature dependences of the dc conductivity for all types of the structures under study are obtained; it is shown that all dependences include two activation portions. For hightemperature portions, the activation energies are determined as 0.85 eV for europium diphthalocyanine with the ortho-bis(oxymethyl)phenyl bridge, 1.135 eV for europium bitrisphthalocyanine with the orthobis(oxymethyl)phenyl bridge, 0.98 eV for europium dinaphthalocyanine, and 1.18 eV for erbium dinaphthalocyanine. For the low-temperature activation portion, it is shown that lanthanide ions and their bond with a ligand make the dominant contribution to the conductivity of the structures under study.
   

1. 
   Вибронные свойства органических полупроводников на основе фталоцианиновых комплексов с несимметричным распределением электронной плотности , (2010)
   аннотация

   
   Посвящена исследованию оптических свойств органических полупроводников на основе ди- и трифтало- цианиновых комплексов лантанидов (III) с несимметричным распределением электронной плотности. Полу- чены твердые пленки дифталоцианина ClPcLutBuPc и трифталоцианина ClPcEuBuPcLuBuPc (ClPc = 2, 3, 9, 10, 16, 17, 23, 24-октахлорфталоцианинат, tBuPc = 2(3), 9(10), 16(17), 23(24)-тетра-третбутилфталоцианинат, BuPc = 2, 3, 9, 10, 16, 17, 23, 24-октабутилфталоцианинат) и исследованы их спектры пропускания в средней ИК-области. Расшифровка спектров пропускания показала, что усложнение структуры молекул фталоцианина приводит к тому, что в области 1400−1450 см−1 изоиндольная группа может проявлять вибронные свойства в виде четырех линий поглощения. В дальней ИК-области обнаружены новые линии поглощения, наличие которых может быть связано с присутствием хлор-углеродных связей.
   

1. 
   EPR and photoluminescence diagnostics of singlet oxygen generation on porous silicon surface , (2009)
   аннотация

   
   Electron paramagnetic resonance and photoluminescence spectroscopy are used to investigate photosensitized generation of singlet oxygen in the porous silicon layers. The singlet oxygen concentration in the samples was estimated at various oxygen pressures. The time of energy transfer from excitons confined in Si nanocrystals to adsorbed O2 molecules on silicon nanocrystal surface and photosensitization efficiency are found to depend on the porosity of the samples. The singlet oxygen generation efficiency increases strongly for porous silicon with high (>80%) porosity.
   

1. 
   Оптические и электрические свойства полупроводниковых структур на основе бутилзамещенных фталоцианинов, содержащих ионы эрбия , (2008)
2. 
   Photoluminescence in Semiconductor Structures Based on Butyl-Substituted Erbium Phthalocyanine Complexes , (2008)
   аннотация

   
   The study is concerned with the luminescence properties of ensembles of semiconductor structures containing organic phthalocyanine molecules with erbium ions as complexing agents. The photoluminescence spectra of the structures of the type of erbium monophthalocyanine, bisphthalocyanine, and triphthalocyanine are recorded. The photoluminescence peaks are detected at the wavelengths 888, 760, and 708 nm (and photon energies 1.4, 1.6, and 1.75 eV) corresponding to electronic transitions within the organic complexes. It is found that, when a metal complexing agent is introduced into the molecular structure of the ligand, the 708 nm luminescence peak becomes unobservable. It is shown that, in the bisphthalocyanine samples, the photoluminescence signal corresponding to transitions from the 4 F 9/2 level of erbium ions is enhanced.
   

1. 
   Silicon nanocrystals as efficient photosensitizer of singlet oxygen for biomedical applications , (2007)
   аннотация

   
   Luminescent silicon nanocrystals (nc-Si) are shown to be efficient photosensitizers of singlet oxygen (SO) generation. Photoluminescence (PL) spectroscopy method is used to study the mechanism and efficiency of the SO photosensitization in gaseous and aqueous ambiences. In vitro experiments demonstrated that the SO, photosensitized by nc-Si dispersed in nutrient solutions, could kill cancer cells. This finding opens a broad opportunity for biomedical applications of nc-Si, e.g. for the photodynamic therapy of cancer or antibacterial treatments.
   
2. 
   Dependence of the singlet oxygen photosensitization efficiency on morphology of porous silicon , (2007)
   аннотация

   
   We investigate the effect of oxygen molecule adsorption on the photoluminescence of porous silicon films of different porosity. The experimental results are explained by the photosensitization of singlet oxygen generation due to the energy transfer from excitons confined in Si nanocrystals to O2 molecules adsorbed on the Si nanocrystal surface. The energy transfer time and photosensitization efficiency are found to depend on porosity of the samples. The singlet oxygen generation efficiency increases strongly for porous silicon with high (> 80%) porosity.We investigate the effect of oxygen molecule adsorption on the photoluminescence of porous silicon films of different porosity. The experimental results are explained by the photosensitization of singlet oxygen generation due to the energy transfer from excitons confined in Si nanocrystals to O2 molecules adsorbed on the Si nanocrystal surface. The energy transfer time and photosensitization efficiency are found to depend on porosity of the samples. The singlet oxygen generation efficiency increases strongly for porous silicon with high (> 80%) porosity.
   

1. 
   Charge Carrier Transport in a Structure with Silicon Nanocrystals Embedded into Oxide Matrix , (2006)
   аннотация

   
   Current–voltage characteristics of Al/SiO 2 / c -Si structures with silicon nanocrystals ( nc -Si) in the oxide layer are studied in a wide temperature range. The analysis based on the experimental data has shown that thermostimulated tunneling via electron states in nc -Si is a most probable mechanism of charge carrier transport in these structures.
   
2. 
   Femtosecond Nanostructuring of Silicon Surfaces , (2006)
   аннотация

   
   Nanostructures were formed upon the irradiation of single-crystal silicon surfaces with femtosecond laser pulses. These nanostructures were detected using scanning electron microscopy, Raman spectroscopy, and a photoluminescence technique.
   
3. 
   Silicon Nanocrystals As Photosensitizers of Active Oxygen for Biomedical Applications , (2006)
   аннотация

   
   Silicon nanocrystals dispersed in water have been used to photosensitize the generation of active oxygen. The photosensitizing efficiency has been estimated through the quenching of the exciton photoluminescence of silicon nanocrystals. Experiments have revealed a strong (up to 80%) decrease in the number of cancer mouse fibroblast cells when they come into contact with photoexcited silicon nanocrystals. The obtained results show that the use of silicon nanocrystals for biomedical applications, in particular, for photodynamic therapy of cancer, is feasible.
   
4. 
   Electron-paramagnetic resonance and photoluminescence study of Si nanocrystals-photosensitizers of singlet oxygen molecules , (2006)
   аннотация

   
   Si nanocrystals formed by electrochemical porosifying of c-Si wafers are investigated by means of the electron-paramagnetic resonance (EPR) and photoluminescence (PL) techniques. The PL spectra and transients give evidence of the photosensitization of singlet oxygen molecules by the energy transfer from excitons confined in Si nanocrystals to oxygen molecules adsorbed on the nanocrystal surfaces. The EPR experiments show that the singlet oxygen generation is accompanied by a slowing down of the spin-spin relaxation time of Si dangling bonds on the nanocrystal surfaces. This effect is explained by the transition of a large part of the adsorbed O2 molecules in their ground (triplet) states to the excited (singlet) ones. The EPR data allow us to estimate the concentration of the photosensitized singlet oxygen molecules to be on the order of 1018 cm3.
   

1. 
   Особенности фотолюминесценции органических молекул в пористом кремнии , (2004)
2. 
   Влияние адсорбции донорных и акцепторных молекул на рекомбинационные свойства кремниевых нанокристаллов , (2004)

1. 
   ОСОБЕННОСТИ ВЗАИМОДЕЙСТВИЯ АДСОРБИРОВАННЫХ ОРГАНИЧЕСКИХ МОЛЕКУЛ С МАТРИЦЕЙ ПОРИСТОГО КРЕМНИЯ , (2003)