Flower-like 3D CuO microsphere acting as photocatalytic water oxidation catalyst

Flower-like 3D CuO microspheres were synthesized and used to photo-catalyze water oxidation under visible light. The structure of the CuO microspheres was characterized by scanning electron microscopy, transmission electron microscopy, infrared, powder X-ray diffraction, electron dispersive spectroscopy, Raman and X-ray photoelectron spectroscopy (XPS). This is the first time that a copper oxide was demonstrated as a photocatalytic water oxidation catalyst under near neutral conditions. The catalytic activity of CuO microspheres in borate buffer shows the best performance with O-2 yield of 11.5%. No change in the surface properties of CuO before and after the photocatalytic reaction was seen by XPS, which showed good catalyst stability. A photocatalytic water oxidation reaction mechanism catalyzed by the CuO microspheres was proposed. (C) 2016, Dalian Institute of Chemical Physics, Chinese Academy of Sciences. Published by Elsevier B.V. All rights reserved.