摘要
Abstract
Fe2O3/g-C3N5 photocatalyst was prepared by solvothermal method,and its performance in methane removal from coal mine gas was studied.X-ray diffraction(XRD),Fourier transform infrared spectroscopy(FTIR),ultraviolet-visible diffuse reflectance spectroscopy(UV-vis DRS),photoluminescence(PL),transient photocurrent spectroscopy(TPC),electrochemical impedance spectroscopy(EIS)and electron spin resonance spectroscopy(ESR)were used to characterize the crystal structure,characteristic absorption bands,spectral absorption,photoelectron-hole recombination,photoelectrochemical properties and active groups of the photocatalyst.The results showed that,under simulated sunlight irradiation for 180 min,the Fe2O3/g-C3N5 photocatalyst had removed 96.8%of CH4(the initial volume fraction of CH4 was 18%),and the removal efficiency of CH4 could still reach 95.8%after 5 cycles,indicative of good photocatalytic activity and stability.That was due to the construction of Z-scheme heterojunction between Fe2O3 and g-C3N5,which effectively promoted the photoelectron-hole separation,broadened the spectral absorption range,and promoted charge transfer.CH4 was attacked by h+to generate·CH3,which was further oxidized by·O2-and·OH to achieve degradation and removal.This work could provide a theoretical basis for photocatalytic removal of CH4 in coal mine gas.关键词
富氮氮化碳/光催化剂/异质结/瓦斯/甲烷Key words
nitrogen-rich carbon nitride/photocatalyst/heterojunction/gas/methane分类
化学化工
