Visible light active heterostructured photocatalyst system based on CuO plate‐like particles and SnO ₂ nanofibers

Abstract

Abstract In this study, CuO–SnO 2 p‐n type heterostructures were produced and tested for the degradation of methylene blue and 4‐nitrophenol under visible light irradiation. CuO particles were produced in plate‐like morphology using hydrothermal synthesis. SnO 2 nanofibers were obtained by electrospinning. Structural, morphological, optical and semiconducting property characterization of heterostructured CuO–SnO 2 and individual phases were performed. The photocatalytic activity was found to change depending on the amount of CuO particles in heterostructured samples. Among others, the sample with 0.35 wt.% CuO–SnO 2 showed the highest photocatalytic efficiency with a degradation rate constant ~2 h −1 . Active specie scavenger tests revealed that the decomposition reaction occurs through direct oxidation mechanism by the holes in the valence band of SnO 2 in pure samples whereas in CuO–SnO 2 samples and radicals also form and involve in the reactions. Further, the photocatalytic degradation mechanism was revealed using relative band potentials and p‐n junctions of the heterostructured photocatalyst.