The synthesis of CB[8]/ZnO composites materials with enhanced photocatalytic activities

• Main Authors: Lan Li, Lin Liu, Zhuang Li, Danling Hu, Chao Gao, Jinyan Xiong, Wei Li
• Format: Article
• Language: English
• Published: Elsevier 2019-05-01
• Series: Heliyon
• Subjects: Materials chemistry
• Online Access: http://www.sciencedirect.com/science/article/pii/S2405844019314033

Enhancing the separation of hole-electron pairs is one of the valid pathway to enhance the photocatalytic degradation performance of semiconductors. In this work, cucurbit[8]uril/zinc oxide (CB[8]/ZnO) composites were prepared. The structure, morphology, surface elements and optical properties of the composite are characterized by powder X-ray diffraction, scanning electron microscopy, Fourier transform infrared spectroscopy, X-ray photoemission spectroscopy, thermogravimetric analysis, and specific surface area measurements. In the photocatalytic degradation of 500 mg/L reactive brilliant red X-3B and 400 mg/L reactive yellow X-RG solutions, the rate constant of the CB[8]/ZnO composite is six times that of pure ZnO. A possible photocatalytic degradation mechanism is proposed. Zn2+ ions chelate with the carbonyl group of CB[8] on the surface of CB[8]/ZnO. Under ultraviolet-visible light irradiation, the generated holes of ZnO are transferred to and trapped on the CB[8] units to facilitate the separation of electron-hole pairs, improving the photocatalytic performance of this system.