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The electrodeposition from room temperature ionic liquids (RTILs) has recently come up as a low-cost technique for the growth of II–VI semiconductor compounds and thin films, some promising alternatives to classical organic or inorganic solvents. As a relatively new field of study, only a few reports exist describing the growth mechanism of electrodeposition from RTILs, especially for CdSe films. In this paper, a new electrochemical method has been developed for the deposition of Cadmium Selenide thin layers onto indium doped tin oxide coated conducting glass (ITO) using an RTIL and an Organic solvent system (Tricaprylmethylammonium chloride/Formamide). Structural properties of prepared films have been investigated by X-ray diffraction (XRD) and micro-Raman analysis which reveal a pure cubic phase with the zinc-blende-type structure and typical peaks of nanostructured CdSe, respectively. Atomic force microscopy (AFM) analysis showed homogenous and smooth surface of the deposited films. UV-vis measurements demonstrated the presence of direct transition with a band gap energy around 1.68 eV. The flat-band potential and carrier density values of CdSe thin film are − 0.667 V and 6. 1 3 × 1 0 1 6 cm − 3 , respectively, as deduced from Mott–Schottky studies. The photoelectrochemical (PEC) behavior of the CdSe thin film exhibited an enhanced photocurrent density at about 0.35 mA/cm2 vs. Ag/AgCl. [ABSTRACT FROM AUTHOR]

Silver-doped zinc oxide (SZO) thin films have been deposited onto indium-doped tin oxide substrates (ITO) using sol–gel spin-coating technique with different Ag doping content (1, 2 and 5% Ag). The effect of silver incorporation on structural, morphological, optical and photoelectrochemical (PEC) properties of the SZO films was investigated. Ag incorporation resulted in an enhanced grain size and thickness of elaborated SZO films. Scanning electron micrographs exhibited a uniform distribution of spherical grains with particle size increment after doping. Band gap energies were found to increase after Ag doping. Photoluminescence (PL) measurements revealed that the energy band gaps of the films were in the UV region. As compared to pure ZnO thin film, the samples are more photoactive, and the film containing 2% Ag yielded the highest photocurrent. A correlation study between PEC and PL measurements of Ag-doped ZnO/ITO photoanode leads to a reverse variation. Charge transfer processes at the ZnO–electrolyte interface were identified by electrochemical impedance spectroscopy. [ABSTRACT FROM AUTHOR]