Surface Enhanced Raman Spectroscopy (SERS) is a powerful tool for investigation of low concentrat... more Surface Enhanced Raman Spectroscopy (SERS) is a powerful tool for investigation of low concentration analytes. To improve this method magnetic properties having nanoparticles were introduced to the system. Magnetic nanoparticles...
In the present work, polycrystalline Bi0.67La0.33Fe0.5Sc0.5O3 thin films were synthesized using a... more In the present work, polycrystalline Bi0.67La0.33Fe0.5Sc0.5O3 thin films were synthesized using a simple and cost-effective chemical solution deposition process employing the spin coating technique. In order to check the feasibility of the fabrication of thin films on various types of substrates, the films were deposited on Pt-coated silicon, silicon, sapphire, corundum, fused silica and glass. Based on the results of thermogravimetric analysis of precursor and thermal stability study, it was determined that the optimal annealing temperature for the formation of perovskite structure is 600 °C. It was observed that the relative intensity of the pseudocubic peaks (001)p and (011)p in the XRD patterns is influenced by the nature of substrates, suggesting that the formed crystallites have some preferred orientation. Roughness of the films was determined to be dependent on the nature of the substrate.
2019 Conference on Lasers and Electro-Optics Europe & European Quantum Electronics Conference (CLEO/Europe-EQEC), 2019
In this paper we demonstrate the fabrication of a true-3D inorganic ceramic with resolution down ... more In this paper we demonstrate the fabrication of a true-3D inorganic ceramic with resolution down to the nanoscale (∼100 nm) using a sol-gel resist precursor. This method has an unrestricted free-form capability, control of the fill-factor, and high fabrication throughput. A systematic study of the proposed approach based on ultrafast laser 3D lithography (also know as 2PP, TPP or MPP [1]) of organicinorganic hybrid solgel resin followed by a heat treatment enabled the formation of inorganic amorphous and crystalline composites guided by the composition of the initial resin. The achieved resolution of 100 nm was obtained for 3D patterns of complex free-form architectures. Fabrication throughput of 50 · 103 voxels per second is achieved [2]; voxel a single volume element recorded by a single pulse exposure. A post-exposure thermal treatment was used to form a ceramic phase, the composition and structure of which were dependent on the temperature and duration of the heat treatment as revealed by Raman micro-spectroscopy. The X-ray diffraction (XRD) showed a gradual emergence of the crystalline phases at higher temperatures with a signature of cristobalite SiO2, a high-temperature polymorph. Also, a tetragonal ZrO2 phase known for its high fracture strength was observed. The illustration of material conversion from hybrid-organic to pure inorganic amorphous/crystalline is depicted in Fig. 1.
Polypyrrole (Ppy) and poly(methylene blue) (PMB) heterostructure (Ppy-PMB) was electrochemically ... more Polypyrrole (Ppy) and poly(methylene blue) (PMB) heterostructure (Ppy-PMB) was electrochemically formed on the indium tin oxide (ITO) coated glass slides, which served as working electrodes. For electropolymerization, a solution containing pyrrole, methylene blue, and a saccharide (lactose, sucrose, or heparin) that served as dopant was used. The aim of this study was to compare the effect of the saccharides (lactose, sucrose, and heparin) on the electrochromic properties of the Ppy-PMB layer. AFM and SEM have been used for the analysis of the surface dominant features of the Ppy-PMB layers. From these images, it was concluded that the saccharides used in this study have a moderate effect on the surface morphology. Electrochromic properties were analyzed with respect to the changes of absorbance of the layer at two wavelengths (668 nm and 750 nm) by changing the pH of the surrounding solution and the potential between +0.8 V and −0.8 V. It was demonstrated that the highest absorbanc...
Conducting polymers have found application in various sensors and biosensors. In this research ac... more Conducting polymers have found application in various sensors and biosensors. In this research achievements of authors in the synthesis and application of conducting polymers in enzymatic glucose biosensors is overviewed and discussed. Some methods of conducting polymer synthesis are outlined and compared. The most attention has been paid to electrochemical, chemical and biochemical synthesis of conducting polymers applied by authors for synthesis of such conducting polymers as polypyrrole, polyaniline, polythiophene, and some others conducting or π-π conjugated polymers. Applicability of conducting polymer based functional layers in the design of electrochemical biosensors is overviewed. Significant attention is focused on the application of enzyme — glucose oxidase (GOx) as the mostly in design of glucose sensors applied biocatalyst.
The thin films of calcium hydroxyapatite were deposited on a stainless steel substrate modified w... more The thin films of calcium hydroxyapatite were deposited on a stainless steel substrate modified with titanium nitride (TiN) using an aqueous sol–gel method and characterized by X-ray diffraction analysis. It was demonstrated for the first time that the formation of calcium hydroxyapatite during heat treatment inhibited the formation of Fe2O3 and promoted the formation of TiO2 on the surface.
Determination of analytes (e.g. glucose) in complex samples (e.g. blood) is one of the challengin... more Determination of analytes (e.g. glucose) in complex samples (e.g. blood) is one of the challenging task of recent bio-analytical chemistry. For this purpose various kinds of sensors are applied, however, the simplest and cheapest sensors, and thus the most widely exploited, are electrochemical enzymatic biosensors. However, these sensors still has number of limitations to overcome in order to demonstrate their practical applicability. One of them is an effective electron transfer from the active center of the redox enzyme to the electrode surface. In this work carbon-based nanostructures have been applied in the design of the electrodes and the parameters, such as an optimal enzyme concentration, the type of the coating and the electrode selectivity have been evaluated.
Plasmonics: Design, Materials, Fabrication, Characterization, and Applications XIX, 2021
The goal of this study is development of ultra-sensitive and reproducible SERS platform based on ... more The goal of this study is development of ultra-sensitive and reproducible SERS platform based on novel magnetoplasmonic nanoparticles produced by laser ablation. The magnetic part of hybrid nanoparticles ensures manipulation of the nanoparticles by magnetic field by arranging them at biological surfaces in a special geometry resulting in high and reproducible SERS. Magneto-plasmonic Au-Fe nanoparticles in colloidal suspension were prepared by picosecond laser ablation of evaporated iron and gold films on glass. The nanoparticles were characterized by UV-visible extinction, high resolution electronic microscopy, and Raman spectroscopy. EDX analysis revealed that the shell of nanoparticles (2−20 nm) consist of iron and the core is composed mostly of gold. The plasmonic behavior of nanoparticles was accessed by analysis of SERS spectra from adsorbed adenine as probe ligand. The fabrication of hybrid nanoparticles by laser ablation offers a new possibility for construction of SERS substrates with tunable optical and magnetic properties for biomedical sensing.
3D Printed Optics and Additive Photonic Manufacturing, 2018
Ceramics as advanced materials play an important role in science and technology as they are mecha... more Ceramics as advanced materials play an important role in science and technology as they are mechanically robust, can withstand immense heat, are chemically inert. Consequently, there is a direct end-user driven need to find ways for efficiently acquiring free-form 3D ceramic structures. Recently, stereo-lithographic 3D printing of hybrid organic-inorganic photo-polymer and subsequent heating was demonstrated to be capable of providing true 3D ceramic and glass structures. Up to now, this was limited to (sub-)millimeter scale and naturally the next step is to acquire functional glass-/ceramic-like 3D structures in micro-/nano-dimensions. In this paper, we explore a possibility to apply ultrafast 3D laser nanolithography followed by heating to acquire ceramic 3D structures down to micro-/nano-dimension. Laser fabrication is employed for the production of initial 3D structures with varying (ranging within hundreds of nm) feature sizes out of hybrid organic-inorganic material SZ2080. Then, a post-fabrication heating at different temperatures up to 1500 °C in an air atmosphere facilitates metal-organic framework decomposition, which results in the glass-ceramic hybrid material. Additionally, annealing procedure densifies the obtained objects providing an extra route for size control. As we show, this can be applied to bulk and free-form objects. We uncover that the geometric downscaling can reach up to 40%, while the aspect ratio of single features, as well as filling ratio of the whole object, remains the same regardless of volume/surface-area ratio. The structures proved to be qualitatively resistant to dry etching, hinting at significantly increased resiliency. Finally, Raman spectrum and X-ray diffraction (XRD) analysis were performed in order to uncover undergoing chemical processes during heat-treatment in order to determine the composition of material obtained. Revealed physical and chemical properties prove the proposed approach paving a route towards 3D opto-structuring of ceramics at the nanoscale for diverse photonic, microfluidic and biomedical applications.
Abstract Electrochromism is the phenomenon, which is based on the change of material color when p... more Abstract Electrochromism is the phenomenon, which is based on the change of material color when particular voltage is applied to electrochemical system. This feature is of high importance for a wide range of actuating devices such as smart windows, screens, thermal modulators and various sensors. During this research we have formed and investigated polypyrrole (Ppy) based layers, which were electrochemically deposited on the indium tin oxide coated glass in the presence of three phenothiazine (PT) derivatives - methylene blue (MB), azure A (AA), and thionine (TH). The surface morphology of the coatings was determined by atomic force microscopy (AFM) and scanning electron microscopy (SEM). It was found that the thickness of the surface irregularities ranged from 1 to 3 µm. Polypyrrole and poly(Azure A) layer (Ppy-PAA) was the thickest one and non-translucent, therefore, it was not suitable for further research. The reflection absorption infrared spectroscopy (RAIRS) was chosen for the evaluation of the layer due to the possibility to measure reflection spectra of thin layers avoiding influence of the glass substrate present under the ITO layer. The polypyrrole and poly(methylene blue) (Ppy-PMB) and polypyrrole and polythionine (Ppy-PTH) layers further were analyzed by cyclic voltammetry and chronoamperometry methods. The applicability of Ppy-PMB, Ppy-PAA, and Ppy-PTH in chemical sensing was evaluated. The investigated polymeric coatings exhibited electrochromic properties (color change at different potential), reacted to pH changes and to ascorbic acid concentration.
In this study, new synthetic approaches for the preparation of thin films of Mg-Al layered double... more In this study, new synthetic approaches for the preparation of thin films of Mg-Al layered double hydroxides (LDHs) have been developed. The LDHs were fabricated by reconstruction of mixed-metal oxides (MMOs) in deionized water. The MMOs were obtained by calcination of the precursor gels. Thin films of sol–gel-derived Mg-Al LDHs were deposited on silicon and stainless-steel substrates using the dip-coating technique by a single dipping process, and the deposited film was dried before the new layer was added. Each layer in the preparation of the Mg-Al LDH multilayers was separately annealed at 70 °C or 300 °C in air. Fabricated Mg-Al LDH coatings were characterized by X-ray diffraction (XRD) analysis, scanning electron microscopy (SEM), and atomic force microscopy (AFM). It was discovered that the diffraction lines of Mg3Al LDH thin films are sharper and more intensive in the sample obtained on the silicon substrate, confirming a higher crystallinity of synthesized Mg3Al LDH. However...
Surface Enhanced Raman Spectroscopy (SERS) is a powerful tool for investigation of low concentrat... more Surface Enhanced Raman Spectroscopy (SERS) is a powerful tool for investigation of low concentration analytes. To improve this method magnetic properties having nanoparticles were introduced to the system. Magnetic nanoparticles...
In the present work, polycrystalline Bi0.67La0.33Fe0.5Sc0.5O3 thin films were synthesized using a... more In the present work, polycrystalline Bi0.67La0.33Fe0.5Sc0.5O3 thin films were synthesized using a simple and cost-effective chemical solution deposition process employing the spin coating technique. In order to check the feasibility of the fabrication of thin films on various types of substrates, the films were deposited on Pt-coated silicon, silicon, sapphire, corundum, fused silica and glass. Based on the results of thermogravimetric analysis of precursor and thermal stability study, it was determined that the optimal annealing temperature for the formation of perovskite structure is 600 °C. It was observed that the relative intensity of the pseudocubic peaks (001)p and (011)p in the XRD patterns is influenced by the nature of substrates, suggesting that the formed crystallites have some preferred orientation. Roughness of the films was determined to be dependent on the nature of the substrate.
2019 Conference on Lasers and Electro-Optics Europe & European Quantum Electronics Conference (CLEO/Europe-EQEC), 2019
In this paper we demonstrate the fabrication of a true-3D inorganic ceramic with resolution down ... more In this paper we demonstrate the fabrication of a true-3D inorganic ceramic with resolution down to the nanoscale (∼100 nm) using a sol-gel resist precursor. This method has an unrestricted free-form capability, control of the fill-factor, and high fabrication throughput. A systematic study of the proposed approach based on ultrafast laser 3D lithography (also know as 2PP, TPP or MPP [1]) of organicinorganic hybrid solgel resin followed by a heat treatment enabled the formation of inorganic amorphous and crystalline composites guided by the composition of the initial resin. The achieved resolution of 100 nm was obtained for 3D patterns of complex free-form architectures. Fabrication throughput of 50 · 103 voxels per second is achieved [2]; voxel a single volume element recorded by a single pulse exposure. A post-exposure thermal treatment was used to form a ceramic phase, the composition and structure of which were dependent on the temperature and duration of the heat treatment as revealed by Raman micro-spectroscopy. The X-ray diffraction (XRD) showed a gradual emergence of the crystalline phases at higher temperatures with a signature of cristobalite SiO2, a high-temperature polymorph. Also, a tetragonal ZrO2 phase known for its high fracture strength was observed. The illustration of material conversion from hybrid-organic to pure inorganic amorphous/crystalline is depicted in Fig. 1.
Polypyrrole (Ppy) and poly(methylene blue) (PMB) heterostructure (Ppy-PMB) was electrochemically ... more Polypyrrole (Ppy) and poly(methylene blue) (PMB) heterostructure (Ppy-PMB) was electrochemically formed on the indium tin oxide (ITO) coated glass slides, which served as working electrodes. For electropolymerization, a solution containing pyrrole, methylene blue, and a saccharide (lactose, sucrose, or heparin) that served as dopant was used. The aim of this study was to compare the effect of the saccharides (lactose, sucrose, and heparin) on the electrochromic properties of the Ppy-PMB layer. AFM and SEM have been used for the analysis of the surface dominant features of the Ppy-PMB layers. From these images, it was concluded that the saccharides used in this study have a moderate effect on the surface morphology. Electrochromic properties were analyzed with respect to the changes of absorbance of the layer at two wavelengths (668 nm and 750 nm) by changing the pH of the surrounding solution and the potential between +0.8 V and −0.8 V. It was demonstrated that the highest absorbanc...
Conducting polymers have found application in various sensors and biosensors. In this research ac... more Conducting polymers have found application in various sensors and biosensors. In this research achievements of authors in the synthesis and application of conducting polymers in enzymatic glucose biosensors is overviewed and discussed. Some methods of conducting polymer synthesis are outlined and compared. The most attention has been paid to electrochemical, chemical and biochemical synthesis of conducting polymers applied by authors for synthesis of such conducting polymers as polypyrrole, polyaniline, polythiophene, and some others conducting or π-π conjugated polymers. Applicability of conducting polymer based functional layers in the design of electrochemical biosensors is overviewed. Significant attention is focused on the application of enzyme — glucose oxidase (GOx) as the mostly in design of glucose sensors applied biocatalyst.
The thin films of calcium hydroxyapatite were deposited on a stainless steel substrate modified w... more The thin films of calcium hydroxyapatite were deposited on a stainless steel substrate modified with titanium nitride (TiN) using an aqueous sol–gel method and characterized by X-ray diffraction analysis. It was demonstrated for the first time that the formation of calcium hydroxyapatite during heat treatment inhibited the formation of Fe2O3 and promoted the formation of TiO2 on the surface.
Determination of analytes (e.g. glucose) in complex samples (e.g. blood) is one of the challengin... more Determination of analytes (e.g. glucose) in complex samples (e.g. blood) is one of the challenging task of recent bio-analytical chemistry. For this purpose various kinds of sensors are applied, however, the simplest and cheapest sensors, and thus the most widely exploited, are electrochemical enzymatic biosensors. However, these sensors still has number of limitations to overcome in order to demonstrate their practical applicability. One of them is an effective electron transfer from the active center of the redox enzyme to the electrode surface. In this work carbon-based nanostructures have been applied in the design of the electrodes and the parameters, such as an optimal enzyme concentration, the type of the coating and the electrode selectivity have been evaluated.
Plasmonics: Design, Materials, Fabrication, Characterization, and Applications XIX, 2021
The goal of this study is development of ultra-sensitive and reproducible SERS platform based on ... more The goal of this study is development of ultra-sensitive and reproducible SERS platform based on novel magnetoplasmonic nanoparticles produced by laser ablation. The magnetic part of hybrid nanoparticles ensures manipulation of the nanoparticles by magnetic field by arranging them at biological surfaces in a special geometry resulting in high and reproducible SERS. Magneto-plasmonic Au-Fe nanoparticles in colloidal suspension were prepared by picosecond laser ablation of evaporated iron and gold films on glass. The nanoparticles were characterized by UV-visible extinction, high resolution electronic microscopy, and Raman spectroscopy. EDX analysis revealed that the shell of nanoparticles (2−20 nm) consist of iron and the core is composed mostly of gold. The plasmonic behavior of nanoparticles was accessed by analysis of SERS spectra from adsorbed adenine as probe ligand. The fabrication of hybrid nanoparticles by laser ablation offers a new possibility for construction of SERS substrates with tunable optical and magnetic properties for biomedical sensing.
3D Printed Optics and Additive Photonic Manufacturing, 2018
Ceramics as advanced materials play an important role in science and technology as they are mecha... more Ceramics as advanced materials play an important role in science and technology as they are mechanically robust, can withstand immense heat, are chemically inert. Consequently, there is a direct end-user driven need to find ways for efficiently acquiring free-form 3D ceramic structures. Recently, stereo-lithographic 3D printing of hybrid organic-inorganic photo-polymer and subsequent heating was demonstrated to be capable of providing true 3D ceramic and glass structures. Up to now, this was limited to (sub-)millimeter scale and naturally the next step is to acquire functional glass-/ceramic-like 3D structures in micro-/nano-dimensions. In this paper, we explore a possibility to apply ultrafast 3D laser nanolithography followed by heating to acquire ceramic 3D structures down to micro-/nano-dimension. Laser fabrication is employed for the production of initial 3D structures with varying (ranging within hundreds of nm) feature sizes out of hybrid organic-inorganic material SZ2080. Then, a post-fabrication heating at different temperatures up to 1500 °C in an air atmosphere facilitates metal-organic framework decomposition, which results in the glass-ceramic hybrid material. Additionally, annealing procedure densifies the obtained objects providing an extra route for size control. As we show, this can be applied to bulk and free-form objects. We uncover that the geometric downscaling can reach up to 40%, while the aspect ratio of single features, as well as filling ratio of the whole object, remains the same regardless of volume/surface-area ratio. The structures proved to be qualitatively resistant to dry etching, hinting at significantly increased resiliency. Finally, Raman spectrum and X-ray diffraction (XRD) analysis were performed in order to uncover undergoing chemical processes during heat-treatment in order to determine the composition of material obtained. Revealed physical and chemical properties prove the proposed approach paving a route towards 3D opto-structuring of ceramics at the nanoscale for diverse photonic, microfluidic and biomedical applications.
Abstract Electrochromism is the phenomenon, which is based on the change of material color when p... more Abstract Electrochromism is the phenomenon, which is based on the change of material color when particular voltage is applied to electrochemical system. This feature is of high importance for a wide range of actuating devices such as smart windows, screens, thermal modulators and various sensors. During this research we have formed and investigated polypyrrole (Ppy) based layers, which were electrochemically deposited on the indium tin oxide coated glass in the presence of three phenothiazine (PT) derivatives - methylene blue (MB), azure A (AA), and thionine (TH). The surface morphology of the coatings was determined by atomic force microscopy (AFM) and scanning electron microscopy (SEM). It was found that the thickness of the surface irregularities ranged from 1 to 3 µm. Polypyrrole and poly(Azure A) layer (Ppy-PAA) was the thickest one and non-translucent, therefore, it was not suitable for further research. The reflection absorption infrared spectroscopy (RAIRS) was chosen for the evaluation of the layer due to the possibility to measure reflection spectra of thin layers avoiding influence of the glass substrate present under the ITO layer. The polypyrrole and poly(methylene blue) (Ppy-PMB) and polypyrrole and polythionine (Ppy-PTH) layers further were analyzed by cyclic voltammetry and chronoamperometry methods. The applicability of Ppy-PMB, Ppy-PAA, and Ppy-PTH in chemical sensing was evaluated. The investigated polymeric coatings exhibited electrochromic properties (color change at different potential), reacted to pH changes and to ascorbic acid concentration.
In this study, new synthetic approaches for the preparation of thin films of Mg-Al layered double... more In this study, new synthetic approaches for the preparation of thin films of Mg-Al layered double hydroxides (LDHs) have been developed. The LDHs were fabricated by reconstruction of mixed-metal oxides (MMOs) in deionized water. The MMOs were obtained by calcination of the precursor gels. Thin films of sol–gel-derived Mg-Al LDHs were deposited on silicon and stainless-steel substrates using the dip-coating technique by a single dipping process, and the deposited film was dried before the new layer was added. Each layer in the preparation of the Mg-Al LDH multilayers was separately annealed at 70 °C or 300 °C in air. Fabricated Mg-Al LDH coatings were characterized by X-ray diffraction (XRD) analysis, scanning electron microscopy (SEM), and atomic force microscopy (AFM). It was discovered that the diffraction lines of Mg3Al LDH thin films are sharper and more intensive in the sample obtained on the silicon substrate, confirming a higher crystallinity of synthesized Mg3Al LDH. However...
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