Electrochemical Fabrication and Characterization of Cu2ZnSnS4 (CZTS) Thin Film Deposits on Gold Substrate for Hydrogen Production

Abstract

In this paper, room temperature one-step electrodeposition of chalcogenide CZTS followed by annealing at different temperatures was studied. The scanning electron microscopy images of the deposits confirmed the presence of agglomerated particles in the deposits. The deposits annealed at [Formula: see text]C did not show the presence of voids whereas deposits annealed at [Formula: see text]C showed severe sulfur loss and were off-stoichiometric. Annealing at [Formula: see text]C resulted in the deposits of compositions closer to the required ratio. Good absorbance over the entire visible range makes both the annealed deposits suitable absorber materials for thin-film photovoltaic cells. Current–voltage characteristics resulted in Ohmic trend and the slope of the plot increased with annealing temperature. The deposits showed good photosensitive behavior where resistance decreased upon shining the light source. The Mott–Schottky plot showed that the deposits were made of positively charged particles. CZTS thin film annealed at [Formula: see text]C provided higher H2 production rate (68.68 [Formula: see text]mol ⋅ [Formula: see text] ⋅ [Formula: see text], which was 32 times higher than that of CZTS annealed at [Formula: see text]C (2.08 [Formula: see text]mol ⋅ [Formula: see text] ⋅ [Formula: see text]. What’s more, photocatalytic activity of CZTS thin film remained 94% after 48 h which confirmed the good stability and reusability of CZTS thin film. CZTS thin film is a potential and durable candidate for photocatalysis.