Highly dispersible and uniform size Cu2ZnSnS4 nanoparticles for photocatalytic application

Abstract

Highly dispersible, uniform size (∼7nm) single-phase Cu2ZnSnS4 nanoparticles have been synthesized by hydrothermal method using non-toxic surfactant (oleic acid). High resolution transmission electron microscopy image indicates good crystallinity of the Cu2ZnSnS4 nanoparticles with the growth along (112) plane. X-ray photoelectron spectroscopy analyses suggested that the formation of with Cu, Zn, and Sn in +1, +2 and +4 oxidation states. The optical absorption spectrum of Cu2ZnSnS4 nanoparticles exhibits an absorption in the visible region and its optical band gap was found to be ∼1.72eV, which could be much more appropriate for photocatalytic application under visible light irradiation. These Cu2ZnSnS4 nanoparticles have been shown high photocatalytic degradation activity of methylene blue (MB) dye in the presence of visible light irradiation. The rate constant (k) value of Cu2ZnSnS4 nanoparticles is found to be 0.0144min−1. We have discussed the mechanism of dye degradation process that drives the photocatalytic degradation process. The reusability of the Cu2ZnSnS4 nanoparticles for the dye degradation is also demonstrated.