Visible-light photocatalytic efficiencies and anti-photocorrosion behavior of CdS/graphene nanocomposites: Evaluation using methylene blue degradation

A series of CdS nanocrystals/graphene (CdS/GR) nanocomposites with various graphene contents were prepared. Their photocatalytic efficiencies and anti-photocorrosion behavior were studied using methylene blue degradation under visible-light irradiation. The results showed that the introduction of graphene improved the migration efficiency of photogenerated carriers and inhibited charge carrier recombination. The photocatalytic efficiencies of the as-prepared CdS/GR nanocomposites were influenced by the graphene content, achieving a maximum at a graphene content of 4.6 wt% (denoted by CdS/GR-4.6%). The anti-photocorrosion behavior of the CdS/GR-4.6% nanocomposite was further investigated using a photoelectrochemical method and X-ray diffraction analysis. The photocorrosion of CdS nanocrystals was effectively suppressed after the introduction of graphene sheets. Compared with bare CdS nanocrystals, the photocurrent of the CdS/GR-4.6% nanocomposites increased 2.3-fold. (C) 2013, Dalian Institute of Chemical Physics, Chinese Academy of Sciences. Published by Elsevier B.V. All rights reserved.