Development and Characterization of Sb₂(SₓSe₁-ₓ)₃ Thin Films and Its Application as a Promising Photocathode

Authors: N. R. Mathews, R. G. Sotelo Marquina, R. G. Avilez García, X. Mathew

Abstract:

Sb₂(SₓSe₁-ₓ)₃ thin films were developed by a single-step electrodeposition process on fluorine-doped SnO₂ conducting substrates. Cyclic voltammetry studies were done to determine the optimum potential for the co-electrodeposition of Sb-S-Se. The deposited films were adherent and uniform, without pin holes. The effect of the deposition potential on the S/Se ratio in the films and the optoelectronic properties was correlated. The results of the structural, morphological and optical properties of the films will be presented. The structural studies using X-ray diffraction and Raman spectroscopy confirmed the formation of orthorhombic antimony sulfide selenide thin films without any impurity phases. The optical band gap of Sb₂(SₓSe₁-ₓ)₃ decreased with the increase of the Se concentration in the films. The capacitance-voltage data showed a negative slope, characteristic of p-type materials. The films deposited at higher negative potentials showed larger carrier concentrations due to their higher Se content. The heterostructure Sb2(S-Se)₃ CdS/Pt demonstrated a photocurrent density of 10 mA cm-² at 0 V vs reversible hydrogen electrode

Keywords: Sb2(SxSe1-x)3, photocathode, chalcogenide thin-films, electrodeposition