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Electrodeposited copper zinc tin sulfide (CZTS) thin films grown on conducting glass substrates are investigated in this report. The photoelectrochemical cell (PEC), optical, structural and morphological properties of the deposited films have been characterized. PEC measurements of the CZTS thin film showed p-type electrical conductivity. Optical measurement showed that the transmittance of CZTS films is observed to about 0.5-3.4% in the wavelength range 300-1100 nm. It is also observed that the absorbance of the CZTS thin films rapidly increases in the wavelength range 580-620 nm and then it decreases slowly. The band gap of the CZTS thin film is observed to be in the range 1.6-2.2 eV. The transmittance and band gap decreases upon annealing at different temperatures but the absorbance and the grain size increases due to the improvement of crystalline quality upon annealing. From the X-ray diffraction study, the CZTS films are found to be polycrystalline with (112), (200), (105), (204), (312), (220) orientations of the tetragonal structure. The average crystallite size is estimated to 23 nm for as-deposited film, 26 nm for annealed at 300 °C and 40 nm for annealed at 350 °C. It is found from SEM study that the precursor film shows non-uniform distribution of agglomerated particles with well-defined boundaries. As the annealing temperature increases, the crystallization of the films is observed to improve, and hence the morphology of as-deposited precursor film is observed to change into the larger flat grains upon annealing. [ABSTRACT FROM AUTHOR]

An electrochemical synthesis route for NiMnGa alloys is presented. Thin films of NiMnGa were fabricated by single step electrodeposition from aqueous electrolytes using direct current over a range of current densities. By electrolyte tuning, homogeneous films with high Ga and Mn content could be achieved at current densities as high as −400 mA cm −2 . Detailed compositional analysis of the alloys showed that growth was homogeneous and oxygen content was minimized. Films plated at very low current densities were found to be nanocrystalline/amorphous. In order to obtain fully crystalline samples, thermal annealing was carried out. Mechanical characterization was assessed by nanoindentation, and the effect of Ga content on mechanical properties was investigated. [ABSTRACT FROM AUTHOR]

Abstract: We fabricate a Cu2ZnSnS4 (CZTS) absorber layer, by using single step electrodeposition of CZTS precursor, deposited at −1.05 V, followed by high temperature annealing in a sulfur atmosphere. X-ray diffraction pattern indicates that the as-grown sample is amorphous in nature, and polycrystalline CZTS thin films with kesterite crystal structure have been obtained by sulfurization from 450 to 580 °C. Surface morphologies of the as-grown sample show some voids with agglomerated particles. After sulfurization, the morphologies of the annealed samples become more uniform, and dense. EDAX study reveals that the sulfurized samples are nearly stoichiometric, being Cu-rich and S-deficient in composition. The band gaps of the annealed samples are found to be in the range from 1.9 to 1.5 eV. [Copyright &y& Elsevier]

Abstract: The Cu2ZnSnS4 (CZTS) thin films have been electrochemically deposited on Mo-coated glass substrate from weak acidic medium (pH 4.5–5) at room temperature. The effect of complexing agent (tri-sodium citrate) on the structural, morphological and compositional properties of CZTS thin films has been investigated. The as-deposited and annealed thin films were characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM),EDAX and X-ray photoelectron spectroscopy (XPS) techniques for their structural, morphological, compositional and chemical properties, respectively. XRD studies reveal that the amorphous nature of as-deposited thin film changes into polycrystalline with kesterite crystal structure after annealing in Ar atmosphere. The film prepared without complexing agent showed well-covered surface morphology on the substrate with some cracks on the surface of the film whereas those prepared using complexing agent, exhibited uneven and slightly porous and some overgrown particles on the surface of the films. After annealing, morphology changes into the flat grains, uniformly distributed over the entire surface of the substrate. The EDAX and XPS study reveals that the films deposited using 0.2M tri-sodium citrate are nearly stoichiometric. [ABSTRACT FROM AUTHOR]

Abstract: The Cu2ZnSnS4 (CZTS) thin films have been electrodeposited onto the Mo coated and ITO glass substrates, in potentiostatic mode at room temperature. The deposition mechanism of the CZTS thin film has been studied using electrochemical techniques like cyclic voltammetery. For the synthesis of these CZTS films, tri-sodium citrate and tartaric acid were used as complexing agents in precursor solution. The structural, morphological, compositional, and optical properties of the CZTS thin films have been studied using X-ray diffraction (XRD), scanning electron microscopy (SEM), EDAX and optical absorption techniques respectively. These properties are found to be strongly dependent on the post-annealing treatment. The polycrystalline CZTS thin films with kieserite crystal structure have been obtained after annealing as-deposited thin films at 550 in Ar atmosphere for 1h. The electrosynthesized CZTS film exhibits a quite smooth, uniform and dense topography. EDAX study reveals that the deposited thin films are nearly stoichiometric. The direct band gap energy for the CZTS thin films is found to be about 1.50eV. The photoelectrochemical (PEC) characterization showed that the annealed CZTS thin films are photoactive. [Copyright &y& Elsevier]