Preparation and characterization of Cu2ZnSnS4 thin films by solvothermal method

The Cu₂ZnSnS₄ thin films have been deposited onto FTO glass substrates by a simple solvothermal method. The films were characterized by X-ray diffraction, scanning electron microscopy, energy dispersive X-ray analyzer, and optical absorption spectroscopy technique, respectively. The influence of the annealing temperature on the structure, morphology, and composition of the films has been studied. The polycrystalline Cu₂ZnSnS₄ thin films crystallized in the tetragonal structure with nearly stoichiometric after annealing at 550 °C in Ar atmosphere for 1h. The analysis of the optical absorption data gave the bandgap energy to be 1.5 eV. The photoelectrochemical characterization showed that the annealed CZTS thin films behaved as p-type semiconductor photoelectrodes.