Preparation of potassium ion doped graphite carbon nitride via molten salt method and its photocatalytic mineralization ability of organic pollutants
HU Shao-zheng1, LI Wei1, GU Gui-zhou1, YUAN Xing-zhou1, LIANG Fei-xue1, WU Guang2
1. College of Chemistry, Chemical Engineering, and Environmental Engineering, Liaoning Shihua University, Fushun 113001, China; 2. School of Chemistry and Materials Sciences, Heilongjiang University, Harbin 150080, China
Abstract：A band gap-tunable potassium doped graphitic carbon nitride (g-C3N4) with enhanced RhB degradation ability was prepared via molten salt method. X-ray diffraction (XRD), UV-Vis spectroscopy, X-ray photoelectron spectroscopy (XPS), N2 adsorption, Photoluminescence (PL) and Electrochemical impedance spectra (EIS) were used to characterize the prepared catalysts. The addition of potassium inhibited the crystal growth of graphitic carbon nitride, enhanced the surface area and increased the separation rate of photogenerated electrons and holes. In addition, by controlling the potassium ion doping amount, the CB and VB potentials of graphitic carbon nitride can be adjusted within a certain range, so that the oxidative degradation reaction of organic pollutants changes from single oxidant (·O2-) reaction to double oxidant (·OH and·O2-) reaction, leading to the promoted degradation and mineralization ability. The RhB degradation rate constant of as-prepared potassium ion doped catalyst arrived 0.022min-1, which is 5 times higher than that of neat g-C3N4. Moreover, the degradation rate of the as-prepared catalyst to other organic pollutants, such as methyl blue and phenol, was also significantly improved by tuning the energy level.
胡绍争, 李薇, 顾贵洲, 苑兴洲, 梁飞雪, 武光. 熔盐法制备K+-g-C3N4及其光催化降解有机污染物性能[J]. 中国环境科学, 2020, 40(7): 3106-3113.
HU Shao-zheng, LI Wei, GU Gui-zhou, YUAN Xing-zhou, LIANG Fei-xue, WU Guang. Preparation of potassium ion doped graphite carbon nitride via molten salt method and its photocatalytic mineralization ability of organic pollutants. CHINA ENVIRONMENTAL SCIENCECE, 2020, 40(7): 3106-3113.
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