Shivaji Sadale | Shivaji University, Kolhapur, India (original) (raw)

Papers by Shivaji Sadale

Advances in Research, 2020

Objective: Nectar is a sweet sustenance substance which organization, shading, flavor, and kind o... more Objective: Nectar is a sweet sustenance substance which organization, shading, flavor, and kind of nectar depend primarily on the blossoms, land districts and atmosphere and bumble bee species. We analyzed physicochemical and sensorial qualities attributed to different honey bee species in western Maharashtra of India. Methodology: Apis dorsata, Cerana indica, Apis florea nectar from various bumble bee species from Kolhapur and Mahabaleshwar locale and remaining sample from market were studied for physicochemical and sensorial evaluation. Results and Discussion: Brix of Cerana indica and Apis florea nectar gives 82.82 and 82.43°B which is higher than Apis dorsata and Market sample Honey. Acidity of the Apis dorsata was 0.38% which is higher than other nectar tests which showed matured marginal and gives the harsh unsuitable taste. Cerana indica test from Kolhapur district contains more sugar content 63.55% which gives dim golden color and better sweet taste increment its general agr...

Current Journal of Applied Science and Technology, 2019

Aims: The aim of this study was to optimize clarification process of the Aloe vera juice followed... more Aims: The aim of this study was to optimize clarification process of the Aloe vera juice followed by its preservation by ohmic heating as no systematic study has been conducted on these aspects. Study Design: The enzymatic clarification method was used for clarification of Aloe vera juice by using the enzyme pectinase. The enzyme concentration, incubation temperature and time were optimized for clarification of juice. The Aloe vera juice was treated at different Time (min) gradients, current, initial temperature and after temperature at particular current gradient and the ohmic heated juice was then stored in sterilized bottles for further analysis. Place and Duration of Study: Experiments were done in Department of Food Science and Technology, Shivaji University, Kolhapur, M.S. (India) and completed within 12 months. Methodology: The optimal conditions for the enzymatic treatment of Aloe vera juice were investigated in order to minimize the turbidity of the juice and maximize the T...

Journal of energy storage, Nov 1, 2023

Vanadium pentoxide thin films are prepared via sol-gel spin coating method. The films coated on F... more Vanadium pentoxide thin films are prepared via sol-gel spin coating method. The films coated on FTO and glass substrates are treated at different temperatures ranging from 250 8C to 400 8C. The structural, optical and electrochemical investigations are made. X-ray diffraction analysis shows the film to be composed of V 2 O 5 in b-phase up to annealing temperature of 350 8C and at 400 8C the structural transformation to a-phase is observed. FTIR spectrum shows the formation of V-O bond. The SEM images reveal the formation of nanopores. Optical absorption studies indicate a band gap of 2.2-2.4 eV. The supercapacitor behaviour is studied using cyclic voltammetery technique and electrochemical impedance analysis. The vanadium pentoxide films annealed at 300 8C for an hour exhibits a maximum specific capacitance of 346 F g À1 at a scan rate of 5 mV s À1 .

Size-dependent electrochemical kinetics of nano-granular WO3 thin films

Solar Energy Materials and Solar Cells

Solar Energy Materials and Solar Cells, 2007

The nucleation and growth mechanism of the electrodeposited zinc oxide thin films on fluorine-dop... more The nucleation and growth mechanism of the electrodeposited zinc oxide thin films on fluorine-doped tin oxide (FTO) coated (10-20 O/cm 2) glass substrates from acetate solution, without and with ex situ oxygen bubbling, has been studied by cyclic voltammetry (CV), chronoamperometry (CA) and scanning electron microscopy (SEM) techniques. Ethylene diamine tetra acetic acid (EDTA) was used as a complexing agent. The cyclic voltammograms exhibit crossover, a characteristic of nucleation process on FTO-coated conducting glass substrates for all the baths bubbled with oxygen. The current transients were analyzed by fitting chronoamperometric data into the Scharifker-Hills nucleation model. The plausible nucleation and growth mechanism is proposed. For mother bath and lower oxygen bubbling time, the nucleation and growth mechanism follows 3D progressive nucleation and growth, which became instantaneous in case of baths for higher oxygen bubbling time. The SEM study showed that the films become compact when the oxygen bubbling time was increased. The thin films were further characterized by X-ray diffraction technique for structural studies and the ZnO film formation was confirmed. With the increase in oxygen bubbling time, the shift in band gap energies from 3.2 to 3.3 eV is observed.

Solar Energy Materials and Solar Cells, 2007

Tin oxide (SnO 2) thin films were prepared by a simple and inexpensive spray pyrolysis technique ... more Tin oxide (SnO 2) thin films were prepared by a simple and inexpensive spray pyrolysis technique from an aqueous solution at various substrate temperatures viz. 300, 400 and 500 1C, and their electrochemical studies have been carried out. The thin films have been optically and electrochemically characterized by means of transmittance, cyclic voltammetry and chronoamperometry. The mechanism of reduction and oxidation reactions that took place during the potential cycling is presented. The samples deposited at 500 1C exhibit better performance in terms of coloration efficiency, reversibility, contrast ratio and response time.

Solar Energy Materials and Solar Cells, 2006

Electrochromic molybdenum oxide-doped iridium oxide thin films were prepared by using a pneumatic... more Electrochromic molybdenum oxide-doped iridium oxide thin films were prepared by using a pneumatic spray pyrolysis technique onto fluorine-doped tin oxide (FTO) coated conducting glass substrates. An aqueous solution of 0.01 M ammonium molybdate was mixed with 0.01 M iridium trichloride in different volume proportions and the resultant solution was used as a precursor for spraying. An aqueous electrolyte (0.5 N H 2 SO 4) was used to study electrochromic properties of thin films using cyclic voltammetry (CV), chronoamperometry (CA) and spectrophotometry. During the potential scan the iridium oxide electrode switches between coloured and bleached state due to Ir +4-Ir +3 intervalency charge transfers. The optical density difference (DOD) l ¼ 630 nm and colouration efficiency was maximum for 2% molybdenum oxide-doped sample. Moreover, loss in charge density during extended cycling is less than undoped and other doped (42%) samples.

Materials Chemistry and Physics, 2003

Iridium oxide thin films with variable thickness were deposited by spray pyrolysis technique (SPT... more Iridium oxide thin films with variable thickness were deposited by spray pyrolysis technique (SPT), onto the amorphous glass substrates kept at 350 • C. The volume of iridium chloride solution was varied to obtain iridium oxide thin films with thickness ranging from 700 to 2250 Å. The effect of film thickness on structural and electrical properties was studied. The X-ray diffraction (XRD) studies revealed that the as-deposited samples were amorphous and those annealed at 600 • C for 3 h in milieu of air were polycrystalline IrO 2. The crystallinity of Ir-oxide films ameliorate with film thickness thereby preferred orientation along (1 1 0) remains unchanged. The infrared spectroscopic results show Ir-O and Ir-O 2 bands. The room temperature electrical resistivity (ρ RT) of these films decreases with increase in film thickness. The p-type semiconductor to metallic transition was observed at 600 • C.

Journal of Materials Science: Materials in Electronics, 2005

Niobium Oxide (Nb 2 O 5) thin films were deposited on the glass substrates, using spray pyrolysis... more Niobium Oxide (Nb 2 O 5) thin films were deposited on the glass substrates, using spray pyrolysis technique. During deposition the preparative parameters like nozzle to substrate distance, spray rate, concentration of the sprayed solution were kept constant at optimized values. The effect of substrate (deposition) temperature (varied between 250 to 450 • C) and post annealing treatment (at temperature 500 • C) on the structural, optical and electrical properties of thin films were studied. Using scanning electron microscopy and X-ray diffraction technique morphological and structural characterizations of the films were carried out. For optical and electrical properties of thin films, optical absorption and two probe electrical resistivity techniques were used. It has been observed that with increase in the substrate temperature films become micro or polycrystalline. Annealed films exhibit higher crystallinity. Other parameters like thickness, electrical resistivity and band gap energy value decrease with increase in substrate temperature.

Electrochimica Acta, 2005

Electrochromic iridium oxide thin films were deposited onto fluorine doped tin oxide coated glass... more Electrochromic iridium oxide thin films were deposited onto fluorine doped tin oxide coated glass substrates from an aqueous iridium chloride solution by pneumatic spray pyrolysis technique. The as-deposited samples were X-ray amorphous. The electrochromic properties of thin films were studied in an aqueous electrolyte (0.5N H 2 SO 4) using cyclic voltammetry (CV), chronoamperometry (CA) and spectrophotometry. Iridium oxide films show pronounced anodic electrochromism owing to Ir +4 ↔ Ir +3 intervalency charge transition. The reversibility of cyclic process in Ir oxide films is found to be higher, which increases with increasing number of colour-bleach cycles.

Systems and set-ups for effective sensing response applications

Sensors for Environment, Health …, 2009

... enforcement and national security _____ *To whom correspondence should be addressed:George Ki... more ... enforcement and national security _____ *To whom correspondence should be addressed:George Kiriakidis, Institute of Electronic Structure and Laser, Foundation for Research & Technology Hellas, Heraklion, Crete, Greece, 71 110; e-mail: kiriakid@iesl.forth.gr ...

Applied Surface Science, 2006

Molybdenum-doped iridium oxide thin films have been deposited onto corning glass-and fluorine-dop... more Molybdenum-doped iridium oxide thin films have been deposited onto corning glass-and fluorine-doped tin oxide coated corning glass substrates at 350 8C by using a pneumatic spray pyrolysis technique. An aqueous solution of 0.01 M ammonium molybdate was mixed with 0.01 M iridium trichloride solution in different volume proportions and the resultant solution was used as a precursor solution for spraying. The asdeposited samples were annealed at 600 8C in air medium for 1 h. The structural, electrical and optical properties of as-deposited and annealed Modoped iridium oxide were studied and values of room temperature electrical resistivity, and thermoelectric power were estimated. The as-deposited samples with 2% Mo doping exhibit more pronounced electrochromism than other samples, including pristine Ir oxide.

Formation of ⊥c texture of tungsten disulfide thin films with nickel

Applied Surface Science, 2007

ABSTRACT The formation of ⊥c texture of WS2 thin films by solid state reaction between the spray ... more ABSTRACT The formation of ⊥c texture of WS2 thin films by solid state reaction between the spray deposited WO3 and gaseous sulfur vapours with Ni interfacial layer has been reported. X-ray diffraction technique has been used to measure the degree of preferred orientation and texture of WS2 films. Scanning electron microscopy, transmission electron microscopy and atomic force microscopy have been used to characterize the microstructure and morphology. The electronic structure and chemical composition was studied using X-ray photoelectron spectroscopy. The WS2 films comprise single crystalline quality hexagonal crystallites of 15μm×15μm size with their basal planes parallel to the substrate. The film consists of turbostratic stacking sequence of 2H and 3R polytypes of WS2. The tungsten-to-sulfur ratio was estimated to be 1:1.8. The various qualitative models used to explain promotional effects are briefly outlined and the plausible underlying mechanism of formation of ⊥c texture with nickel, in this study, is given.

Applied Surface Science, 2005

Electrochromic iridium oxide thin films were prepared by using a simple and inexpensive spray pyr... more Electrochromic iridium oxide thin films were prepared by using a simple and inexpensive spray pyrolysis technique onto fluorine doped tin oxide (FTO)-coated glass substrates, from iridium chloride solution. The substrate temperature was varied between 250 and 400 8C. The as-deposited samples were amorphous. The electrochromic properties of thin films were studied in aqueous electrolyte (0.5N H 2 SO 4) using cyclic voltammetry (CV), chronoamperometry (CA) and spectroelectrochemical techniques. The films exhibit anodic electrochromism upon intercalation and deintercalation of H + ions. The colouration efficiency at 630 nm was calculated and found maximum for I 250 sample, owing its hydration.

Applied Surface Science, 2005

TiO 2-doped WO 3 thin films were deposited onto fluorine-doped tin oxide coated conducting glass ... more TiO 2-doped WO 3 thin films were deposited onto fluorine-doped tin oxide coated conducting glass substrates using spray pyrolysis technique at 525 8C. The volume percentage of TiO 2 dopant was varied from 13% to 38%. The thin film samples were transparent, uniform and strongly adherent to the substrates. Electrochromical properties of TiO 2-doped WO 3 thin films were studied with the help of cyclic voltammetry (CV), chronoamperometry (CA) and chronocoulometry (CC) techniques. It has been found that TiO 2 doping in WO 3 enhances its electrochromic performance. Colouration efficiency becomes almost double and samples exhibit increasingly high reversibility with TiO 2 doping concentrations, in the studied range.

Synthesis of electrochromic tin oxide thin films with faster response by spray pyrolysis

Applied Surface Science, 2007

... Applied Surface Science Volume 253, Issue 20, 15 August 2007, Pages 8560-8567. ... RF magnetr... more ... Applied Surface Science Volume 253, Issue 20, 15 August 2007, Pages 8560-8567. ... RF magnetron sputtering, Polycrystalline: DP = 4 mTorr (dense); DP = 30 mTorr (porous); t = 0.22–0.32 μm ... PC, PW = −1.4 to +1.4 (NHE), CV featureless in TBAP/PC; increased current in LiClO 4 ...

Applied Surface Science, 2011

A simple and inexpensive spray pyrolysis technique (SPT) was employed for the synthesis of nanocr... more A simple and inexpensive spray pyrolysis technique (SPT) was employed for the synthesis of nanocrystalline zinc oxide (ZnO) thin films onto soda lime glass and tin doped indium oxide (ITO) coated glass substrates at different substrate temperatures ranging from 300 • C to 500 • C. The synthesized films were polycrystalline, with a (0 0 2) preferential growth along c-axis. SEM micrographs revealed the uniform distribution of spherical grains of about 80-90 nm size. The films were transparent with average visible transmittance of 85% having band gap energy 3.25 eV. All the samples exhibit room temperature photoluminescence (PL). A strong ultraviolet (UV) emission at 398 nm with weak green emission centered at 520 nm confirmed the less defect density in the samples. Moreover, the samples are photoelectrochemically active and exhibit the highest photocurrent of 60 A, a photovoltage of 280 mV and 0.23 fill factor (FF) for the Zn 450 films in 0.5 M Na 2 SO 4 electrolyte, when illuminated under UV light.

Iridium oxide thin films with variable thickness were deposited by spray pyrolysis technique (SPT... more Iridium oxide thin films with variable thickness were deposited by spray pyrolysis technique (SPT), onto the amorphous glass substrates kept at 350 • C. The volume of iridium chloride solution was varied to obtain iridium oxide thin films with thickness ranging from 700 to 2250 Å. The effect of film thickness on structural and electrical properties was studied. The X-ray diffraction (XRD) studies revealed that the as-deposited samples were amorphous and those annealed at 600 • C for 3 h in milieu of air were polycrystalline IrO 2. The crystallinity of Ir-oxide films ameliorate with film thickness thereby preferred orientation along (1 1 0) remains unchanged. The infrared spectroscopic results show Ir-O and Ir-O 2 bands. The room temperature electrical resistivity (ρ RT) of these films decreases with increase in film thickness. The p-type semiconductor to metallic transition was observed at 600 • C.

Journal of Materials Science: …, 2005

Niobium Oxide (Nb 2 O 5) thin films were deposited on the glass substrates, using spray pyrolysis... more Niobium Oxide (Nb 2 O 5) thin films were deposited on the glass substrates, using spray pyrolysis technique. During deposition the preparative parameters like nozzle to substrate distance, spray rate, concentration of the sprayed solution were kept constant at optimized values. The effect of substrate (deposition) temperature (varied between 250 to 450 • C) and post annealing treatment (at temperature 500 • C) on the structural, optical and electrical properties of thin films were studied. Using scanning electron microscopy and X-ray diffraction technique morphological and structural characterizations of the films were carried out. For optical and electrical properties of thin films, optical absorption and two probe electrical resistivity techniques were used. It has been observed that with increase in the substrate temperature films become micro or polycrystalline. Annealed films exhibit higher crystallinity. Other parameters like thickness, electrical resistivity and band gap energy value decrease with increase in substrate temperature.

Applied Surface Science, 2011

A simple and inexpensive spray pyrolysis technique (SPT) was employed for the synthesis of nanocr... more A simple and inexpensive spray pyrolysis technique (SPT) was employed for the synthesis of nanocrystalline zinc oxide (ZnO) thin films onto soda lime glass and tin doped indium oxide (ITO) coated glass substrates at different substrate temperatures ranging from 300 °C to 500 °C. The synthesized films were polycrystalline, with a (0 0 2) preferential growth along c-axis. SEM micrographs revealed the uniform distribution of spherical grains of about 80–90 nm size. The films were transparent with average visible transmittance of 85% having band gap energy 3.25 eV. All the samples exhibit room temperature photoluminescence (PL). A strong ultraviolet (UV) emission at 398 nm with weak green emission centered at 520 nm confirmed the less defect density in the samples. Moreover, the samples are photoelectrochemically active and exhibit the highest photocurrent of 60 μA, a photovoltage of 280 mV and 0.23 fill factor (FF) for the Zn450 films in 0.5 M Na2SO4 electrolyte, when illuminated under...

Advances in Research, 2020

Objective: Nectar is a sweet sustenance substance which organization, shading, flavor, and kind o... more Objective: Nectar is a sweet sustenance substance which organization, shading, flavor, and kind of nectar depend primarily on the blossoms, land districts and atmosphere and bumble bee species. We analyzed physicochemical and sensorial qualities attributed to different honey bee species in western Maharashtra of India. Methodology: Apis dorsata, Cerana indica, Apis florea nectar from various bumble bee species from Kolhapur and Mahabaleshwar locale and remaining sample from market were studied for physicochemical and sensorial evaluation. Results and Discussion: Brix of Cerana indica and Apis florea nectar gives 82.82 and 82.43°B which is higher than Apis dorsata and Market sample Honey. Acidity of the Apis dorsata was 0.38% which is higher than other nectar tests which showed matured marginal and gives the harsh unsuitable taste. Cerana indica test from Kolhapur district contains more sugar content 63.55% which gives dim golden color and better sweet taste increment its general agr...

Current Journal of Applied Science and Technology, 2019

Aims: The aim of this study was to optimize clarification process of the Aloe vera juice followed... more Aims: The aim of this study was to optimize clarification process of the Aloe vera juice followed by its preservation by ohmic heating as no systematic study has been conducted on these aspects. Study Design: The enzymatic clarification method was used for clarification of Aloe vera juice by using the enzyme pectinase. The enzyme concentration, incubation temperature and time were optimized for clarification of juice. The Aloe vera juice was treated at different Time (min) gradients, current, initial temperature and after temperature at particular current gradient and the ohmic heated juice was then stored in sterilized bottles for further analysis. Place and Duration of Study: Experiments were done in Department of Food Science and Technology, Shivaji University, Kolhapur, M.S. (India) and completed within 12 months. Methodology: The optimal conditions for the enzymatic treatment of Aloe vera juice were investigated in order to minimize the turbidity of the juice and maximize the T...

Journal of energy storage, Nov 1, 2023

Vanadium pentoxide thin films are prepared via sol-gel spin coating method. The films coated on F... more Vanadium pentoxide thin films are prepared via sol-gel spin coating method. The films coated on FTO and glass substrates are treated at different temperatures ranging from 250 8C to 400 8C. The structural, optical and electrochemical investigations are made. X-ray diffraction analysis shows the film to be composed of V 2 O 5 in b-phase up to annealing temperature of 350 8C and at 400 8C the structural transformation to a-phase is observed. FTIR spectrum shows the formation of V-O bond. The SEM images reveal the formation of nanopores. Optical absorption studies indicate a band gap of 2.2-2.4 eV. The supercapacitor behaviour is studied using cyclic voltammetery technique and electrochemical impedance analysis. The vanadium pentoxide films annealed at 300 8C for an hour exhibits a maximum specific capacitance of 346 F g À1 at a scan rate of 5 mV s À1 .

Size-dependent electrochemical kinetics of nano-granular WO3 thin films

Solar Energy Materials and Solar Cells

Solar Energy Materials and Solar Cells, 2007

The nucleation and growth mechanism of the electrodeposited zinc oxide thin films on fluorine-dop... more The nucleation and growth mechanism of the electrodeposited zinc oxide thin films on fluorine-doped tin oxide (FTO) coated (10-20 O/cm 2) glass substrates from acetate solution, without and with ex situ oxygen bubbling, has been studied by cyclic voltammetry (CV), chronoamperometry (CA) and scanning electron microscopy (SEM) techniques. Ethylene diamine tetra acetic acid (EDTA) was used as a complexing agent. The cyclic voltammograms exhibit crossover, a characteristic of nucleation process on FTO-coated conducting glass substrates for all the baths bubbled with oxygen. The current transients were analyzed by fitting chronoamperometric data into the Scharifker-Hills nucleation model. The plausible nucleation and growth mechanism is proposed. For mother bath and lower oxygen bubbling time, the nucleation and growth mechanism follows 3D progressive nucleation and growth, which became instantaneous in case of baths for higher oxygen bubbling time. The SEM study showed that the films become compact when the oxygen bubbling time was increased. The thin films were further characterized by X-ray diffraction technique for structural studies and the ZnO film formation was confirmed. With the increase in oxygen bubbling time, the shift in band gap energies from 3.2 to 3.3 eV is observed.

Solar Energy Materials and Solar Cells, 2007

Tin oxide (SnO 2) thin films were prepared by a simple and inexpensive spray pyrolysis technique ... more Tin oxide (SnO 2) thin films were prepared by a simple and inexpensive spray pyrolysis technique from an aqueous solution at various substrate temperatures viz. 300, 400 and 500 1C, and their electrochemical studies have been carried out. The thin films have been optically and electrochemically characterized by means of transmittance, cyclic voltammetry and chronoamperometry. The mechanism of reduction and oxidation reactions that took place during the potential cycling is presented. The samples deposited at 500 1C exhibit better performance in terms of coloration efficiency, reversibility, contrast ratio and response time.

Solar Energy Materials and Solar Cells, 2006

Electrochromic molybdenum oxide-doped iridium oxide thin films were prepared by using a pneumatic... more Electrochromic molybdenum oxide-doped iridium oxide thin films were prepared by using a pneumatic spray pyrolysis technique onto fluorine-doped tin oxide (FTO) coated conducting glass substrates. An aqueous solution of 0.01 M ammonium molybdate was mixed with 0.01 M iridium trichloride in different volume proportions and the resultant solution was used as a precursor for spraying. An aqueous electrolyte (0.5 N H 2 SO 4) was used to study electrochromic properties of thin films using cyclic voltammetry (CV), chronoamperometry (CA) and spectrophotometry. During the potential scan the iridium oxide electrode switches between coloured and bleached state due to Ir +4-Ir +3 intervalency charge transfers. The optical density difference (DOD) l ¼ 630 nm and colouration efficiency was maximum for 2% molybdenum oxide-doped sample. Moreover, loss in charge density during extended cycling is less than undoped and other doped (42%) samples.

Materials Chemistry and Physics, 2003

Iridium oxide thin films with variable thickness were deposited by spray pyrolysis technique (SPT... more Iridium oxide thin films with variable thickness were deposited by spray pyrolysis technique (SPT), onto the amorphous glass substrates kept at 350 • C. The volume of iridium chloride solution was varied to obtain iridium oxide thin films with thickness ranging from 700 to 2250 Å. The effect of film thickness on structural and electrical properties was studied. The X-ray diffraction (XRD) studies revealed that the as-deposited samples were amorphous and those annealed at 600 • C for 3 h in milieu of air were polycrystalline IrO 2. The crystallinity of Ir-oxide films ameliorate with film thickness thereby preferred orientation along (1 1 0) remains unchanged. The infrared spectroscopic results show Ir-O and Ir-O 2 bands. The room temperature electrical resistivity (ρ RT) of these films decreases with increase in film thickness. The p-type semiconductor to metallic transition was observed at 600 • C.

Journal of Materials Science: Materials in Electronics, 2005

Niobium Oxide (Nb 2 O 5) thin films were deposited on the glass substrates, using spray pyrolysis... more Niobium Oxide (Nb 2 O 5) thin films were deposited on the glass substrates, using spray pyrolysis technique. During deposition the preparative parameters like nozzle to substrate distance, spray rate, concentration of the sprayed solution were kept constant at optimized values. The effect of substrate (deposition) temperature (varied between 250 to 450 • C) and post annealing treatment (at temperature 500 • C) on the structural, optical and electrical properties of thin films were studied. Using scanning electron microscopy and X-ray diffraction technique morphological and structural characterizations of the films were carried out. For optical and electrical properties of thin films, optical absorption and two probe electrical resistivity techniques were used. It has been observed that with increase in the substrate temperature films become micro or polycrystalline. Annealed films exhibit higher crystallinity. Other parameters like thickness, electrical resistivity and band gap energy value decrease with increase in substrate temperature.

Electrochimica Acta, 2005

Electrochromic iridium oxide thin films were deposited onto fluorine doped tin oxide coated glass... more Electrochromic iridium oxide thin films were deposited onto fluorine doped tin oxide coated glass substrates from an aqueous iridium chloride solution by pneumatic spray pyrolysis technique. The as-deposited samples were X-ray amorphous. The electrochromic properties of thin films were studied in an aqueous electrolyte (0.5N H 2 SO 4) using cyclic voltammetry (CV), chronoamperometry (CA) and spectrophotometry. Iridium oxide films show pronounced anodic electrochromism owing to Ir +4 ↔ Ir +3 intervalency charge transition. The reversibility of cyclic process in Ir oxide films is found to be higher, which increases with increasing number of colour-bleach cycles.

Systems and set-ups for effective sensing response applications

Sensors for Environment, Health …, 2009

... enforcement and national security _____ *To whom correspondence should be addressed:George Ki... more ... enforcement and national security _____ *To whom correspondence should be addressed:George Kiriakidis, Institute of Electronic Structure and Laser, Foundation for Research & Technology Hellas, Heraklion, Crete, Greece, 71 110; e-mail: kiriakid@iesl.forth.gr ...

Applied Surface Science, 2006

Molybdenum-doped iridium oxide thin films have been deposited onto corning glass-and fluorine-dop... more Molybdenum-doped iridium oxide thin films have been deposited onto corning glass-and fluorine-doped tin oxide coated corning glass substrates at 350 8C by using a pneumatic spray pyrolysis technique. An aqueous solution of 0.01 M ammonium molybdate was mixed with 0.01 M iridium trichloride solution in different volume proportions and the resultant solution was used as a precursor solution for spraying. The asdeposited samples were annealed at 600 8C in air medium for 1 h. The structural, electrical and optical properties of as-deposited and annealed Modoped iridium oxide were studied and values of room temperature electrical resistivity, and thermoelectric power were estimated. The as-deposited samples with 2% Mo doping exhibit more pronounced electrochromism than other samples, including pristine Ir oxide.

Formation of ⊥c texture of tungsten disulfide thin films with nickel

Applied Surface Science, 2007

ABSTRACT The formation of ⊥c texture of WS2 thin films by solid state reaction between the spray ... more ABSTRACT The formation of ⊥c texture of WS2 thin films by solid state reaction between the spray deposited WO3 and gaseous sulfur vapours with Ni interfacial layer has been reported. X-ray diffraction technique has been used to measure the degree of preferred orientation and texture of WS2 films. Scanning electron microscopy, transmission electron microscopy and atomic force microscopy have been used to characterize the microstructure and morphology. The electronic structure and chemical composition was studied using X-ray photoelectron spectroscopy. The WS2 films comprise single crystalline quality hexagonal crystallites of 15μm×15μm size with their basal planes parallel to the substrate. The film consists of turbostratic stacking sequence of 2H and 3R polytypes of WS2. The tungsten-to-sulfur ratio was estimated to be 1:1.8. The various qualitative models used to explain promotional effects are briefly outlined and the plausible underlying mechanism of formation of ⊥c texture with nickel, in this study, is given.

Applied Surface Science, 2005

Electrochromic iridium oxide thin films were prepared by using a simple and inexpensive spray pyr... more Electrochromic iridium oxide thin films were prepared by using a simple and inexpensive spray pyrolysis technique onto fluorine doped tin oxide (FTO)-coated glass substrates, from iridium chloride solution. The substrate temperature was varied between 250 and 400 8C. The as-deposited samples were amorphous. The electrochromic properties of thin films were studied in aqueous electrolyte (0.5N H 2 SO 4) using cyclic voltammetry (CV), chronoamperometry (CA) and spectroelectrochemical techniques. The films exhibit anodic electrochromism upon intercalation and deintercalation of H + ions. The colouration efficiency at 630 nm was calculated and found maximum for I 250 sample, owing its hydration.

Applied Surface Science, 2005

TiO 2-doped WO 3 thin films were deposited onto fluorine-doped tin oxide coated conducting glass ... more TiO 2-doped WO 3 thin films were deposited onto fluorine-doped tin oxide coated conducting glass substrates using spray pyrolysis technique at 525 8C. The volume percentage of TiO 2 dopant was varied from 13% to 38%. The thin film samples were transparent, uniform and strongly adherent to the substrates. Electrochromical properties of TiO 2-doped WO 3 thin films were studied with the help of cyclic voltammetry (CV), chronoamperometry (CA) and chronocoulometry (CC) techniques. It has been found that TiO 2 doping in WO 3 enhances its electrochromic performance. Colouration efficiency becomes almost double and samples exhibit increasingly high reversibility with TiO 2 doping concentrations, in the studied range.

Synthesis of electrochromic tin oxide thin films with faster response by spray pyrolysis

Applied Surface Science, 2007

... Applied Surface Science Volume 253, Issue 20, 15 August 2007, Pages 8560-8567. ... RF magnetr... more ... Applied Surface Science Volume 253, Issue 20, 15 August 2007, Pages 8560-8567. ... RF magnetron sputtering, Polycrystalline: DP = 4 mTorr (dense); DP = 30 mTorr (porous); t = 0.22–0.32 μm ... PC, PW = −1.4 to +1.4 (NHE), CV featureless in TBAP/PC; increased current in LiClO 4 ...

Applied Surface Science, 2011

A simple and inexpensive spray pyrolysis technique (SPT) was employed for the synthesis of nanocr... more A simple and inexpensive spray pyrolysis technique (SPT) was employed for the synthesis of nanocrystalline zinc oxide (ZnO) thin films onto soda lime glass and tin doped indium oxide (ITO) coated glass substrates at different substrate temperatures ranging from 300 • C to 500 • C. The synthesized films were polycrystalline, with a (0 0 2) preferential growth along c-axis. SEM micrographs revealed the uniform distribution of spherical grains of about 80-90 nm size. The films were transparent with average visible transmittance of 85% having band gap energy 3.25 eV. All the samples exhibit room temperature photoluminescence (PL). A strong ultraviolet (UV) emission at 398 nm with weak green emission centered at 520 nm confirmed the less defect density in the samples. Moreover, the samples are photoelectrochemically active and exhibit the highest photocurrent of 60 A, a photovoltage of 280 mV and 0.23 fill factor (FF) for the Zn 450 films in 0.5 M Na 2 SO 4 electrolyte, when illuminated under UV light.

Iridium oxide thin films with variable thickness were deposited by spray pyrolysis technique (SPT... more Iridium oxide thin films with variable thickness were deposited by spray pyrolysis technique (SPT), onto the amorphous glass substrates kept at 350 • C. The volume of iridium chloride solution was varied to obtain iridium oxide thin films with thickness ranging from 700 to 2250 Å. The effect of film thickness on structural and electrical properties was studied. The X-ray diffraction (XRD) studies revealed that the as-deposited samples were amorphous and those annealed at 600 • C for 3 h in milieu of air were polycrystalline IrO 2. The crystallinity of Ir-oxide films ameliorate with film thickness thereby preferred orientation along (1 1 0) remains unchanged. The infrared spectroscopic results show Ir-O and Ir-O 2 bands. The room temperature electrical resistivity (ρ RT) of these films decreases with increase in film thickness. The p-type semiconductor to metallic transition was observed at 600 • C.

Journal of Materials Science: …, 2005

Niobium Oxide (Nb 2 O 5) thin films were deposited on the glass substrates, using spray pyrolysis... more Niobium Oxide (Nb 2 O 5) thin films were deposited on the glass substrates, using spray pyrolysis technique. During deposition the preparative parameters like nozzle to substrate distance, spray rate, concentration of the sprayed solution were kept constant at optimized values. The effect of substrate (deposition) temperature (varied between 250 to 450 • C) and post annealing treatment (at temperature 500 • C) on the structural, optical and electrical properties of thin films were studied. Using scanning electron microscopy and X-ray diffraction technique morphological and structural characterizations of the films were carried out. For optical and electrical properties of thin films, optical absorption and two probe electrical resistivity techniques were used. It has been observed that with increase in the substrate temperature films become micro or polycrystalline. Annealed films exhibit higher crystallinity. Other parameters like thickness, electrical resistivity and band gap energy value decrease with increase in substrate temperature.

Applied Surface Science, 2011

A simple and inexpensive spray pyrolysis technique (SPT) was employed for the synthesis of nanocr... more A simple and inexpensive spray pyrolysis technique (SPT) was employed for the synthesis of nanocrystalline zinc oxide (ZnO) thin films onto soda lime glass and tin doped indium oxide (ITO) coated glass substrates at different substrate temperatures ranging from 300 °C to 500 °C. The synthesized films were polycrystalline, with a (0 0 2) preferential growth along c-axis. SEM micrographs revealed the uniform distribution of spherical grains of about 80–90 nm size. The films were transparent with average visible transmittance of 85% having band gap energy 3.25 eV. All the samples exhibit room temperature photoluminescence (PL). A strong ultraviolet (UV) emission at 398 nm with weak green emission centered at 520 nm confirmed the less defect density in the samples. Moreover, the samples are photoelectrochemically active and exhibit the highest photocurrent of 60 μA, a photovoltage of 280 mV and 0.23 fill factor (FF) for the Zn450 films in 0.5 M Na2SO4 electrolyte, when illuminated under...