Effect of calcination on the photocatalytic performance of CdS under visible light irradiation

The photocatalytic activity of cadmium sulfide (CdS) under visible light irradiation was evaluated by degrading methylene blue (MB). Upon calcination in air/O-2 atmosphere, the photocatalytic activity of CdS was enhanced by eliminating the trap energy levels. Meanwhile, the effect of cadmium oxide (CdO) on the photocatalytic activity of CdS was also studied by in situ forming CdO on the surface of CdS. CdO blocked the light absorption of CdS. which decreased the photocatalytic activity of CdS. (C) 2010 Elsevier B.V. All rights reserved.