Preparation and characterization of ZnIn2S4 thin films deposited by spray pyrolysis for hydrogen production

Thin films of ZnIn2S4 were deposited onto indium-doped tin oxide (ITO)-coated glass substrates from a mixed aqueous solution of ZnCl2, InCl3 and (NH2)2CS by a simple and economical spray pyrolysis technique. Structural, morphologic and optical properties of the deposited films were characterized by XRD, SEM, and UV–vis spectra. Moreover, the electrochemical and photoelectrochemical properties were studied via Mott–Schottky method, current–voltage measurement, and photocurrent spectrum measurement. It was found that ZnIn2S4 films can be prepared by spray pyrolysis and the grain size obtained was about 120–200 nm in diameter. The deposited films have a cubic spinel structure and the optical band gap is about 2.1 eV. The results of electrochemical and photoelectrochemical characteristics show that ZnIn2S4 is a potential material for splitting water to produce hydrogen using solar energy.