Growth of the Electrodeposited NiX2 (X= Te, Se) Thin Films

Abstract

Thin films of nickel chalcogenide, NiX₂ (X= Te, Se) have been electrosynthesized on indium-tin-oxide (ITO) coated glass substrates. The films were characterized for their structural, morphological and compositional characteristics. Consisting of transition metals and chalcogenides (S, Se and Te), they show promising solar absorbent properties such as semiconducting band gap, well adhesion to substrate and good conversion with better cost-effective. Cyclic voltammetry experiments have been done prior to electrodeposition in order to get the electrodeposition potential range where the observable reduction range is between -0.9-(-1.1) V. Their optical and semiconducting parameters were also analysed in order to determine the suitability of the thin films for photoelectrochemical (PEC) / solar cell applications. Structural analysis via X-ray diffraction (XRD) analysis reveals that the films are polycrystalline in nature. Scanning electron microscope (SEM) studies reveals that the films were adherent to the substrate with uniform and pin-hole free. Compositional analysis via energy dispersive X-ray (EDX) technique confirms the presence of Ni, Te, and Se elements in the films. The optical studies show that the films are of direct bandgap. Results on the semiconductor parameters analysis of the films showed that the nature of the Mott-Schottky plots indicates that the films obtained are of p-type material.