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To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.solener.2009.12.009 Byline: S.D. Delekar (a), M.K. Patil (a), B.V. Jadhav (b), K.R. Sanadi (b), P.P. Hankare (b) Keywords: Cadmium lead chalcogenide; Chemical synthesis; X-ray diffraction; Mott-Schottky plot; Photoelectrochemical studies Abstract: Optimum composition Cd.sub.0.7Pb.sub.0.3Se thin films have been deposited using the chemical bath containing cadmium sulfate octahydrate, lead nitrate, tartaric acid, potassium hydroxide, ammonia, and sodium selenosulfate onto fluorine-doped tin oxide glass substrate. The various deposition parameters such as composition of reactive bath, pH of the solution, deposition temperature, deposition time, speed of rotation, etc. have been optimized for obtaining good quality film. X-ray diffraction studies revealed the polycrystalline nature of sample with the solid solution of lead (II) ions in CdSe host lattice, having a hexagonal phase structure. Scanning electron micrograph suggested that the grains were non-uniformly distributed over the substrate surface. Film composition was determined by atomic absorption spectroscopy as well as energy dispersive X-ray atomic spectroscopy. Optical absorption data showed the presence of direct transition with energy band gap 1.80eV for the deposited thin films. The dark specific conductance of Cd.sub.0.7Pb.sub.0.3Se thin films was found to the order of 10.sup.-6 (I[c]cm).sup.-1 having n-type semiconducting nature. Photoelectrochemical characterization was carried out using sulfide/polysulfide electrolyte with 1.401% efficiency. Author Affiliation: (a) Department of Chemistry, Dr. Babasaheb Ambedkar Marathwada University, Aurangabad, Sub-center Osmanabad 413 501, Maharashtra, India (b) Solid State Research Laboratory, Department of Chemistry, Shivaji University, Kolhapur 416 004, Maharashtra, India Article History: Received 1 September 2009; Revised 19 November 2009; Accepted 12 December 2009 Article Note: (miscellaneous) Communicated by: Associate Editor Takhir Razykov

Abstract: Colloidal iron-doped (0.0–3.0mol%) TiO2 nanoparticles have been synthesized using sol–gel method and characterized by thermogravimetric analysis, powder XRD, IR spectroscopy, Raman spectroscopy, and transmission electron microscopy (TEM). The characteristic features of nanocrystalline TiO2 in tetragonal anatase phase were confirmed by powder XRD studies with Rietveld refinement. Rietveld refinement data gave 2.59, 3.21 value of R B for pure TiO2 and 3.0mol% Fe:TiO2 nanoparticles, respectively. Raman bands at 639cm−1, 517cm−1, and 395cm−1 further confirmed the pure anatase phase in all samples. TEM pictures revealed the non-spherical nanoparticles having sizes in between 7 and 14nm. Surface area and pore volume for the samples were in the range of 150–87m2/g and 0.35–0.21cm3/g, respectively. The magnetic and optical properties of the nanoparticles were investigated by using SQUID magnetometer and UV–vis spectroscopy. The undoped titania nanoparticles were diamagnetic; whereas all doped titania samples were paramagnetic. The optical band gap of titania nanoparticles were found to decrease with the increase in iron content in host lattice. The photocatalytic performance of the iron-doped TiO2 nanoparticles for the conversions of p-nitrobenzaldehyde to p-nitrobenzoic acid as well as photodegradation of Rhodamine 6G was also investigated. [Copyright &y& Elsevier]

Abstract: Thin films of CdIn2S4 have been deposited on to stainless steel and fluorine-doped tin oxide (FTO)-coated glass substrates from aqueous acidic bath using an electrodeposition technique. Ethylene diamine tetra-acetic acid (EDTA) disodium salt is used as complexing agent to obtain good-quality deposits by controlling the rate of the reaction. The different preparative parameters like concentration of bath, deposition time, bath temperature, pH of the bath have been optimized by the photoelectrochemical (PEC) technique in order to get good-quality photosensitive material. Different techniques have been used to characterize CdIn2S4 thin films. Optical absorption shows the presence of direct transition with band gap energy 2.17eV. The X-ray diffraction (XRD) analysis of the as-deposited and annealed films showed the presence of polycrystalline nature. Energy-dispersive analysis by X-ray (EDAX) study for the sample deposited at optimized preparative parameters shows that the In-to-Cd ratio is almost 2 and S-to-Cd ratio is almost 4. Scanning electron microscopy (SEM) for samples deposited at optimized preparative parameters reveals that spherical grains are uniformly distributed over the surface of the substrate indicates the well-defined growth of polycrystalline CdIn2S4 thin film. PEC characterization of the films is carried out by studying photoresponse, spectral response and photovoltaic output characteristics. The fill factor (ff) and power conversion efficiency (η) of the cell are 69 and 2.94%, respectively. [Copyright &y& Elsevier]

Abstract: Molybdenum disulphide thin films were deposited using chemical bath deposition method on non-conducting glass substrate using tartaric acid as a complexing agent at 363K. The films were characterized by X-ray diffraction, scanning electron microscopy, optical absorption and electrical measurements. X-ray diffraction pattern shows that polycrystalline with hexagonal structure. The direct optical band gap was found to be 1.8eV. Electrical measurement suggests that specific conductance was found in the order of 10−5 to 10−2 (Ωcm)−1 and showing n-type conduction mechanism. [Copyright &y& Elsevier]

Abstract: Thin films of ZrSe2 have been prepared on stainless steel and fluorine-doped tin oxide-coated glass substrates using electrodeposition technique at potentiostatic mode. Double-distilled water containing precursors Zr and Se with ethylene diamine tetra-acetic acid disodium salt as a complexing agent was used to obtain good quality deposits by controlling the rate of reaction. The preparative parameters such as concentration of bath, deposition time, bath temperature, pH of the bath and annealing temperature have been optimized using photoelectrochemical (PEC) technique. The films deposited at optimum preparative parameters are annealed at different temperatures. The film annealed at 200°C shows more photosensitivity. The as-deposited and annealed films at 200°C have been characterized by X-ray diffraction (XRD), energy dispersive analysis by X-ray (EDAX), optical absorption and scanning electron microscopy (SEM). The XRD analysis of the as-deposited and annealed films showed the presence of polycrystalline nature with hexagonal crystal structure. EDAX study reveals that deposited films are almost stoichiometric. Optical absorption study shows the presence of direct transition and band gap energies are found to be 1.5 and 1.38eV, respectively, for the as-deposited and annealed films. SEM study revels that the grains are uniformly distributed over the surface of substrate for the as-deposited as well as annealed film, which indicates formation of good and compact type of crystal structure. [Copyright &y& Elsevier]