The effect of the selenization process on grain size and performance of CuIn(Sx,Se1−x)2 counter electrodes

Abstract

CuIn(S_x,Se_1−x)₂ thin films were fabricated using S²⁻ capped CuInS₂ nanoparticles and a post-selenizing process. The different thermal annealing technologies in selenization resulted in obvious distinction in CuIn(S_x,Se_1−x)₂ grain size and degree of crystallinity. The nanoparticle-derived CuIn(S_x,Se_1−x)₂ thin films were used as counter electrodes in dye-sensitized solar cells and detailed analyses of the counter electrodes using current–voltage (J–V), cyclic voltammetry (CV), as well as electrochemical impedance spectroscopy (EIS) were conducted to investigate the influence of the grain size and crystallinity on the catalytic and electrical conductivity properties of the CuIn(S_x,Se_1−x)₂ thin films.