Antimony selenide thin films by electrodeposition. Influence of deposition conditions and post-deposition thermal treatment on physical and photoelectrochemical properties

Herein, Sb${}_2$Se${}_3$ thin films are obtained by the electrodeposition technique from a single bath on fluorine-doped tin oxide (FTO) substrates. The electrodeposition conditions such as precursor concentration and applied potential, as well as the annealing temperature, and its influence on the structural, morphological, optical, and photoelectrochemical properties are analyzed. From the cyclic voltammetry measurements, the range of deposition potential is established and from the sweep rate variation, an irreversible and diffusion-controlled process is assumed. With the chronoamperometric curves, an instantaneous nucleation is concluded. The Se/Sb ratio variation of the precursor solutions demonstrate that the 0.7 ratio is optimal to obtain Sb${}_2$Se${}_3$ stoichiometric thin films. The conductivity decreases with the increase of the deposition potential, while the highest photosensitivity is obtained with the film deposited at -0.75 V versus the saturated calomel electrode. Regarding the annealing temperature, a compact homogeneous film is obtained in the range from 325 to 425 °C. Therefore, the suitable properties of Sb${}_2$Se${}_3$ films obtained by electrodeposition and the establishment of optimized deposition conditions for its use in photoelectrochemical cells (PECs) are demonstrated. (© 2022 Wiley‐VCH GmbH)