Visible light photocatalytic degradation of methylene blue by SnO2 quantum dots prepared via microwave-assisted method

• Main Authors: Liu, Xinjuan, Pan, Likun, Chen, Taiqiang, Li, Jinliang, Yu, Kai, Sun, Zhuo, Sun, Changqing
• Other Authors: School of Electrical and Electronic Engineering
• Format: Article
• Language: English
• Published: 2013
• Subjects: DRNTU::Science::Chemistry::Physical chemistry::Catalysis
• Online Access: https://hdl.handle.net/10356/101893; http://hdl.handle.net/10220/16924
• Institution: Nanyang Technological University

SnO2 quantum dots (QDs) were successfully synthesized via a microwave-assisted reaction of a SnO2 precursor in an aqueous solution using a microwave system. The morphology, structure and photocatalytic performance in the degradation of methylene blue (MB) were characterized by scanning electron microscopy, transmission electron microscopy, energy dispersive X-ray spectroscopy, X-ray diffraction spectroscopy, UV-vis absorption/reflectance spectroscopy and electrochemical impedance spectroscopy, respectively. The results show that the SnO2 QDs synthesized at a pH value of 5 exhibit an optimal photocatalytic performance with a MB degradation rate of 90% at 240 min under visible light irradiation due to their easier adsorption of pollutants, higher visible light absorption and lower electron–hole pair recombination.