LIDong-mei,ZHANGBo-wen,JIANGShu-xian,et al.Synthesis of MnO2/g-C3N4 Nanocomposite and Its Photocatalytic Properties[J].China Water & Wastewater,2022,38(13):83-89.
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Synthesis of MnO2/g-C3N4 Nanocomposite and Its Photocatalytic Properties

China Water & Wastewater[ISSN:1000-4062/CN:12-1073/TU] volume: 第38卷 Number: 第13期 Page: 83-89 Column: Date of publication: 2022-07-01
Author(s):
LI　Dong-mei1;  ZHANG　Bo-wen1; 2;  JIANG　Shu-xian1;  XIE　Zhen-yu3;  WANG　Yi-zhi4;  HUANG　Yi1;  LI　Shu-bin1;  LONG　Si-yu1
（1. School of Civil and Transportation Engineering， Guangdong University of Technology， Guangzhou 510006， China； 2. Guangzhou Urban Planning & Design Survey Research Institute， Guangzhou 510006， China； 3. Department of Physics， Fudan University， Shanghai 200433， China； 4. Massachusetts Institute of Technology， America）
Keywords:
graphite carbon nitride modification;  morphology control;  MnO2 doping;  visible light activity;  methyl orange;  photocatalytic performance
Abstract:
Graphite carbon nitride (g-C3N4) was modified by morphology regulation of Na2SO4 and doping of MnO2. Multi-morphological MnO2/g-C3N4 composite photocatalyst (MCN) was prepared by hydrothermal method, the optimum synthesis conditions were discussed, and the microstructure, light absorption capacity and methyl orange (MO) photocatalytic degradation performances of MCN with different morphologies were investigated. The optimum synthesis conditions of MCN were as follows: the dosage of Na2SO4, g-C3N4 and KMnO4 were 0.04 g/L, 0.6 g/L and 0.12 g/L, respectively, the reaction temperature was 80 ℃ and the reaction time was 4 h. The doping of MnO2 significantly improved the photocatalytic activity of g-C3N4. MCN had a photocatalytic degradation efficiency of MO up to 97.34%, while that of g-C3N4 was only 54.39%. MCN had high visible light response activity, the maximum absorption sideband was 486 nm, and the band gap (Eg) was only 2.40 eV (Eg of g-C3N4 was 2.61 eV). MCN had high crystallinity, good purity and stable photocatalytic performance. The photocatalytic degradation efficiency of MO still reached 96.34% after 5 times of reuse. Different dosages of Na2SO4 were capable of adjusting the morphology of MCN, and then improved its photocatalytic activity. The photocatalytic efficiency of spherical MCN for MO degradation was higher than that of rod MCN (the former was 97.34% and the latter was 87.21%). The photocatalytic degradation mechanism of MCN was that MO was decomposed by the active agents ·OH and ·O2- produced by light.
Last Update: 2022-07-01