Synthesis of Cu2ZnSnS4 thin film from mixed solution of Cu2SnS3 nanoparticles and Zn ions

The Cu2ZnSnS4 thin film was prepared by a facile solution method without vacuum environment and toxic substance. The formation mechanism of the film was studied by transmission electron microscopy (TEM), X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS), and Raman scattering measurements. Through cyclic voltammetry and photo-electricity tests, the electrocatalytic activity of the prepared film as the counter electrode of dye-sensitized solar cell was also studied. The results show that the mixed precursor solution mainly consists of Cu2SnS3 nanoparticles and Zn ions. After 550 °C annealing process on the precursor film prepared from the mixed solution, Cu2ZnSnS4 thin film is obtained. Besides, it is found that the prepared Cu2ZnSnS4 thin film has the electrocatalytic activity toward the redox reaction of I3−/I− and the dye-sensitized solar cell with the prepared Cu2ZnSnS4 thin film as the counter electrode achieves the efficiency of 1.09%.