Highly efficient photocatalysis toward tetracycline of nitrogen doped carbon quantum dots sensitized bismuth tungstate based on interfacial charge transfer

In this study, a novel N-CQDs/Bi2WO6 was synthesized through a facile hydrothermal method. Multiple techniques were applied to investigate the structures, morphologies, optical and electronic properties and photocatalytic performance of as-prepared samples. The results indicated that the hybrid materials were formed with N-CQDs attached on the surface of sphere-like Bi2WO6. The photocatalytic activity of N-CQDs/Bi2WO6 materials was evaluated sufficiently by using tetracycline (TC) as target organic pollutant. N-CQDs/Bi2WO6-5 displayed superior photocatalytic efficiency with nearly 97% removal of TC in 25 min and 86.37% mineralization in 90 min. The degradation reaction coefficient (kobs) was approximately two times higher than pure Bi2WO6 as a result of the synergistic effects of N-CQDs and Bi2WO6. Increased light harvesting capacity, excellent electron transfer ability and improved molecular oxygen activation ability were obtained in N-CQDs/Bi2WO6 hybrid materials caused by N-CQDs. The present study demonstrated that N-CQDs modification was an effective way to improve photocatalytic efficiency, which can be extended to a general strategy for other semiconductors. The study indicated that novel N-CQDs/Bi2WO6 has a great potential for rapid and efficient treatment of organic pollutants in water. (C) 2017 Elsevier Inc. All rights reserved.