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In this work, tungsten oxide (WO3) films were deposited at room temperature and annealed for 2 h at 400°C. The electrochromic and electrochemical properties were studied for two different electrolytes. The films were deposited at different oxygen flow rates of 2, 4, and 6 standard cubic centimeters per minute (SCCM). X-ray diffraction analysis revealed structural characterization of amorphous and crystalline phases. UV-visible spectroscopy optical transmittance revealed 91% transmittance, and energy-dispersive x-ray spectroscopy (EDS) analysis revealed the absence of impurities and the presence of W and O. An electrochemical analyzer was used to characterize the deposited and annealed WO3 films immersed in the two different electrolyte solutions (H2SO4 and LiClO4 with oxygen flow rates ranging from 2 SCCM to 6 SCCM). It was found that the H2SO4 electrolyte of an annealed WO3 thin film at 2 SCCM demonstrated high coloring efficiency of 50.18 cm2/C, and the LiClO4 electrolyte of an annealed WO3 thin film at 4 SCCM demonstrated high coloring efficiency of 20.06 cm2/C. [ABSTRACT FROM AUTHOR]

The columnar growth angle-dependent tungsten oxide (WO3) thin films were grown by using the Glancing angle sputter deposition (GLAD) technique with varying different substrate angles (00, 700, 750, and 800) on Fluorine-doped tin oxide (FTO) and Corning glass (CG) corning glass substrates at room temperature. The surface morphology, crystallographic structure, optical, and electrochemical properties were determined using X-ray diffraction (XRD), Field emission scanning electron microscopy (FE-SEM), Ultraviolet–Visible (UV–Vis) spectrometer, and electrochemical analyzer, respectively. The structural properties reveal that the films are amorphous in nature. FE-SEM studies observed the columnar growth of the nano-rods and surface porosity. The optical transmittance of the deposited films was decreased from 83 to 78%, and the optical bandgap decreased from 3.08 to 2.88 eV with increasing GLAD angle. The electrochemical studies reveal that the GLAD angle influenced the coloration efficiency (CE). The highest CE of 32 cm2/C at 600 nm and highest Diffusion coefficient (DC) of 6.529 × 10–9 cm2 s−1 of the films was observed for the films deposited at an angle of 750. [ABSTRACT FROM AUTHOR]

In the past few decades, there has been a jet of interest in adopting tungsten oxide (WO3) thin films as an active layer in electrochromic applications. The central objective of this work is to optimize the deposition rate for E-beam fabricated WO3 thin films yielding an idealized thin film towards profound electrochromic applications. In this regard WO3 thin films were fabricated at three deposition rates 0.5Ao/s, 1.5Ao/s and 3Ao/s on fluorine-doped tin oxide (FTO) coated substrates and corning glass substrates, using e-beam evaporation technique. Films were fully characterized for morphological, structural, optical, electrochemical and electrochromic attributes by Scanning Electron Microscope (SEM), X-ray Diffractometer (XRD), UV–Visible spectroscopy, Cyclic Voltametric (CV) characterization techniques, respectively. SEM characterization stipulated the formation of nanospheres which grew as nanoclusters at a deposition rate of 1.5Ao/s. Energy dispersive spectroscopy (EDS) analysis diagnosticate tungsten and oxygen as two elements present in appropriate atomic percentage values revealing towards purity of the films. XRD analysis postulated towards the amorphous nature of all the as deposited films. Optical transmittance of as deposited films varied from 60 to 65% within the wavelength range of 400 nm to 600 nm. Optical energy band gap value was least at 3.11 eV for the film grown at deposition rate 1.5Ao/s. Highest coloration efficiency and diffusion co-efficient were found to be 17.50 cm2/C and 3.26 × 10–4 cm2/s, respectively, for the film fabricated at deposition rate of 1.5Ao/s. Overall it was witnessed that all the characterization techniques were judiciously whispering to contemplate 1.5Ao/s as an optimized deposition rate to fabricate WO3 thin film towards profound electrochromic application under present experimental condition. [ABSTRACT FROM AUTHOR]

We present the surface and interfacial chemical analysis of sputter deposited TiNi thin films over Si (100) substrates using Rutherford backscattering spectrometry (RBS), secondary ionization mass spectrometry (SIMS), and grazing incidence x-ray diffraction analysis. Upon annealing to high temperatures, significant diffusion of Ni into the Si substrate was observed. The analysis of the RBS and SIMS spectra confirm the net movement of the film species into the substrate. Further, we discuss the formation mechanism and the composition distribution surrounding the TiNi/Si interface that proves conducive for the nucleation and growth of the detected nickel silicide compound. [ABSTRACT FROM AUTHOR]

Tungsten oxide (WO 3) thin films were deposited on Fluorine Doped Tin Oxide (FTO) and Corning Glass (CG) glass substrate by DC magnetron sputtering. The annealing temperature was varied to study its effect on surface morphology, structural, electrochromic (EC), and optical properties and these are investigated by Scanning Electron Microscope (SEM), X-ray Diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), Raman spectroscopy, Cyclic voltammetry, and ultraviolet (UV) spectroscopy. From SEM analysis WO 3 thin films annealed at 27 °C, 100 °C, 200 °C, and 300 °C were shown to crack free after that cracked film was observed for 400 °C. From the XRD investigation that the WO 3 thin films annealed at 27 °C, 100 °C, 200 °C, and 300 °C were amorphous and crystallized at 400 °C. The optical band gap (Eg) of WO 3 films was decreased from 2.98 eV to 2.30 eV with an increase in annealed temperature. The coloration efficiency (CE) was observed at 51.26 cm2/C at 300 °C and 35.06 cm2/C at 400 °C and the lowest diffusion coefficient was observed at 5.86 × 10−10 cm2/s at 400 °C. On coloring efficiency, which can be very important in electrochromic (EC) applications, post-annealing has been seen to have a strong influence. [ABSTRACT FROM AUTHOR]

Zinc oxide nanostructured thin films were deposited at different substrate temperatures on a glass substrate with spray pyrolysis method. The effect of substrate temperature on microstructural, morphological, optical properties of the thin films has been studied systematically using X-ray diffraction (XRD), Raman spectroscopy, atomic force microscopy, scanning electron microscopy (SEM) and UV-Vis spectroscopy. The XRD pattern shows polycrystalline nature and films were crystallized in the wurtzite phase type. Electron-phonon-coupling in zinc oxide thin films was analyzed by Raman spectra at room temperature. SEM micrographs depicted that the substrate temperature influenced the growth of the thin films. Root-mean-square roughness of the thin films was measured using atomic force microscopy. The optical spectra of the ZnO thin films measured in the UV-Vis range. As the substrate temperature increased from 275 to 425 °C, optical band gap was found to decrease from 3.10 to 2.96 eV. Sensitivity and selectivity of the samples were tested at room temperature with respect to different volatile organic gases like benzene, toluene and xylene. Recovery and response times were determined using transient response curve with xylene as the test gas. [ABSTRACT FROM AUTHOR]

The effect of stoichiometry on the coloration efficiency (η) and cycling life of MoO3 films has been investigated and underlying reasons discussed in the paper. Optical studies reveal that as-deposited and 150 °C annealed films are nonstoichiometric while films deposited by activated reactive evaporation are stoichiometric. Nonstoichiometry in unintercalated MoO3 is associated with lower valence states of Mo is responsible for absorption in the 400–1000-nm spectral region. It is found that this nonstoichiometry affects η and the cycling life of the films adversely. [ABSTRACT FROM AUTHOR]

Ag nanoparticles (NPs) embedded in a zirconium oxide matrix in the form of Ag:ZrO nanocomposite (NC) thin films were synthesized by using the sol-gel technique followed by thermal annealing. With the varying of the concentration of Ag precursor and annealing conditions, average sizes (diameters) of Ag nanoparticles (NPs) in the nanocomposite film have been varied from 7 to 20 nm. UV-VIS absorption studies reveal the surface plasmon resonance (SPR)-induced absorption in the visible region, and the SPR peak intensity increases with the increasing of the Ag precursor as well as with the annealing duration. A red shift in SPR peak position with the increase in the Ag precursor concentration confirms the growth of Ag NPs. Surface topographies of these NC films showed that deposited films are dense, uniform, and intact during the variation in annealing conditions. The magnitude and sign of absorptive nonlinearities were measured near the SPR of the Ag NPs with an open-aperture z-scan technique using a nanosecond-pulsed laser. Saturable optical absorption in NC films was identified having saturation intensities in the order of 10 W/m. Such values of saturation intensities with the possibility of size-dependent tuning could enable these NC films to be used in nanophotonic applications. [ABSTRACT FROM AUTHOR]

Abstract: The development of commercially viable “green products”, based on natural resources for the matrices and reinforcements, in a wide range of applications, is on the rise. The present paper focuses on Sterculia urens short fiber reinforced pure cellulose matrix composite films. The morphologies of the untreated and 5% NaOH (alkali) treated S. urens fibers were observed by SEM. The effect of 5% NaOH treated S. urens fiber (5, 10, 15 and 20% loading) on the mechanical properties and thermal stability of the composites films is discussed. This paper presents the developments made in the area of biodegradable S. urens short fiber/cellulose (SUSF/cellulose) composite films, buried in the soil and later investigated by the (POM), before and after biodegradation has taken place. SUSF/cellulose composite films have great potential in food packaging and for medical applications. [Copyright &y& Elsevier]

The paper describes the determination and depth profiling of oxygen in thin oxide films using O(p,α)N nuclear reaction. The excitation function of O(p,α)N nuclear reaction exhibits a resonance at 629 keV and a plateau at 730 keV with uniform cross-section. The resonance is used to determine the depth profile of oxygen in films while the plateau, to estimate its overall concentration. The resonance, characterized by a width of 2.1 keV enables high-depth resolution (~20 nm) measurements and has a probing depth of more than a micron. The paper presents depth profile measurements of oxygen in several metal oxide films (SiO, TiO and HfO) using this resonance. Possible interferences arising from N(p,α)C, F(p,α)O and B(p,α)2α nuclear reactions are also discussed. It has been shown that it can serve as a suitable alternative to 3.05 MeV O(α,α)O resonant scattering which is generally used for depth profiling oxygen. It is, in fact, more reliable and precise in materials that witness significant large angle multiple scattering. It can also be advantageously used to monitor O, when used as a tracer. [ABSTRACT FROM AUTHOR]

The effect of various concentrations of Y-doped SnO 2 thin films (Y: SnO 2) on structural, optical, and electrical properties was investigated. XRD showed the polycrystalline tetragonal structure of all the films. SEM analysis showed homogenous growth of the films with spherical structure. XPS revealed the oxidation states of Sn, Y, and O, also it provides the presence of oxygen vacancies in Y: SnO 2 films. The UV–visible spectrometer studies showed that all the films were above 76% of optical transmittance in the visible region. The optical band gap energy was found to be 3.91 eV for pure SnO 2 , whereas Y: SnO 2 films have shown a decrease of band gap with Y content and reached down to 3.74 eV in 5 at% Y: SnO 2 film. The 3 at% Y: SnO 2 film showed the lowest sheet resistance (R sh) of 34.2 Ω/Sq and the highest figure of merit (ɸ) of 3.55 × 10−3 Ω−1 among the others. [ABSTRACT FROM AUTHOR]

In the present work we prepared Aluminum doped Zinc Oxide (AZO) thin films from powder targets. Various concentrations (W/W percentages) of Al 2 O 3 such as1%, 2%, 3%, 4%, 5%, 6%, 7% and 8% were mixed in ZnO powder and made in the form of a 3 inch disc target. These ceramic targets are sputtered in RF magnetron sputtering unit for the deposition of AZO thin films. Optical and electrical properties are analyzed to get an optimized percentage of mixing for achieving high transparency and low resistivity. At Al 2 O 3 percentage of 3% there is a considerable decrement in the resistivity, and at 7% there is a considerable decrease in the optical transmittance. Mobility and carrier concentration are increasing with Al 2 O 3 percentage. Bandgap of the films is observed to be decreasing with increasing the Al 2 O 3 percentage. [ABSTRACT FROM AUTHOR]

Abstract: Thin films of Zn1−x Mg x O have been deposited using the chemical spray pyrolysis method. The variations in the chemical and physical properties of Zn1−x Mg x O layers deposited with Mg-compositions in the range, 0≤x≤0.3, were investigated with respect to the deposition conditions. The Zn0.76Mg0.24O layers were used as buffer layers in thin film solar cells with the configuration, glass/Mo/CuIn0.8Ga0.2Se2/Zn0.76Mg0.24O/ZnO:Ga/Cu–Au using sprayed p-CuIn0.8Ga0.2Se2 (CIGS) as an absorber layer and sprayed n-ZnO:Ga as a window layer. The devices were characterized using current–voltage, capacitance–voltage and spectral response measurements. The best devices had a solar conversion efficiency of 3.9% with quantum efficiencies >70%. This is the first time such a device has been made in which all the layers were produced using spray pyrolysis. [Copyright &y& Elsevier]

We synthesized different concentrations of Bi (1, 2, 3, 4, and 5 at %) doped SnO 2 (Bi:SnO 2) thin films using the sol-gel spin coating method. The XRD studies confirmed that all deposited films exhibit polycrystalline tetragonal rutile structure. Raman spectra displayed three fundamental bands at 473, 631, and 774 cm−1, which correspond to the Raman modes E g , A 1g , and B 2g. The average transmittance is above 76% for all films. The optical bandgap energy increased from 3.91 eV for pure SnO 2 to 4.22 eV for 3 at% Bi:SnO 2 film and slightly decreased for 4 and 5 at % Bi:SnO 2 films. The sheet resistance (R sh) and resistivity (ρ) values decreased up to 38.8 Ω/□ and 1.62 × 10−3 Ω-cm, respectively, in 3 at % Bi: SnO 2 thin film, and then slightly increased for 4 and 5 at % Bi: SnO 2 films. • Bi-doped ed SnO2 films were deposited on glass substrate using the spin coating method. • The average optical transmittance is > 76% of Bi-doped SnO2 films. • The higher optical band gap value (4.22 eV) is found in 3 at% Bi: SnO2 film. • The lowest sheet resistance (Rsh) value of 38.8 Ω/□ found in 3 at % Bi: SnO2 film. [ABSTRACT FROM AUTHOR]

In the present work, various concentrations of Ti (1, 2, 3, 4 and 5 at %) doped SnO 2 thin films were grown onto glass substrate using cost effective sol-gel spin coating method and subsequently investigated the effect of Ti doping concentration on structural, optical and electrical properties. X-ray diffraction studies revealed that all deposited films exhibit polycrystalline tetragonal rutile structure with fundamental orientation peak along (110) direction. Moreover, Ti doped SnO 2 films were started growing along (211) direction and it was more pronounced with increasing of Ti concentration. The average grain size was decreased with the increase of Ti concentration, confirmed by XRD and AFM studies. The UV–visible spectrometer measurements shown that the average transmittance of un-doped SnO 2 film was above 85%, whereas Ti doped SnO 2 films were found to be a decrease of transmittance up to 77% in 5 at% Ti:SnO 2 film. The optical band gap energy values were considerably decreased from 3.91 to 3.73 eV with increase of Ti content. Further, the sheet resistance (R sh) and resistivity (ρ) values were found to be decreased with the increase of Ti doping up to 3 at % then it was slightly increased in 4 and 5 at % of Ti:SnO 2 films. The efficiency parameter figure of merit (φ) was also estimated for all deposited films with the function of Ti doping. • Ti doped SnO2 films were deposited on glass substrate using spin coating method. • The average optical transmittance is >77% of Ti doped SnO2 films. • The optical band gap value is decreased from 3.91 to 3.73 eV in Ti:SnO2 films. • The lowest sheet resistance (Rsh) value of 38.6 Ω/□ found in 3 at % Ti:SnO2 film. • The higher figure of merit (ɸ = 3.66 × 10-3 Ω-) was found in 2 at% Ti:SnO2 film. [ABSTRACT FROM AUTHOR]