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基于表面活性剂十六烷基三甲基溴化铵为液晶模板,以四氯化钛为钛源,导电碳毡为载体,通过超声波辅助水热法(ultrasound-assisted hydrothermal method,UH)制备介孔二氧化钛/导电碳毡复合体材料(mesoporous titania/conductive carbon felt,MPT/CCF)(UH-MPT/CCF),为了探讨其结构与光电催化活性,直接采用水热法制备介孔二氧化钛/导电碳毡(H-MPT/CCF)和无孔二氧化钛/导电碳毡(no porous titania/conductive carbon felt,NPT/CCF)复合体材料,利用XRD、XPS、SEM、TEM、TG-DTA、N2吸附-脱附等方法对样品结构进行表征,以气相苯甲醛为目标降解物,研究UH-MPT/CCF的光电催化性能及其对气相苯甲醛的降解机理。结果表明,UH-MPT/CCF材料通过介孔化增加了活性中心(·OH和Ti3+),通过CCF的负载提高了对目标降解物的吸附富集,通过偏电压促进光生电子-空穴对的分离,在这三方的协同作用下UH-MPT/CCF对苯甲醛在100 min内降解率为83.9%,分别是H-MPT/CCF、NPT/CCF和P25/CCF的1.38、1.75和2.38倍。气相苯甲醛光电催化降解产生的主要中间产物是苯、1,3-己二烯-5-炔,以及少量的3,3,5-三甲基环己烯、2,3-二甲基-1,3-庚二烯、3-甲基-3-环己烯-1-醇等。根据GC/MS分析结果,进一步提出了气相苯甲醛的降解机理。
Based on the surfactant cetyltrimethylammonium bromide as the liquid crystal template, titanium tetrachloride as the titanium source and the conductive carbon felt as the carrier, the ultrasound-assisted hydrothermal method (UH) In order to investigate its structure and photoelectrocatalytic activity, mesoporous titania / conductive carbon felt (MPT / CCF) (UH-MPT / CCF) (H-MPT / CCF) and non-porous titania / conductive carbon felt (NPT / CCF) composites were synthesized and characterized by XRD, XPS, SEM, TEM, TG- And other methods to characterize the structure of the sample, the gas phase benzaldehyde as the target degradation products, research UH-MPT / CCF photoelectrocatalytic properties and degradation of benzaldehyde gas phase mechanism. The results showed that the UH-MPT / CCF materials increased the active centers (· OH and Ti3 +) through mesoporosity, and enhanced the adsorption and enrichment of the target degradants through the CCF loading, and promoted the photogenerated electron-hole pairs Under these synergistic effects, the degradation rate of benzaldehyde by UH-MPT / CCF was 83.9% in 100 min, which was 1.38, 1.75 and 2.38 times of that of H-MPT / CCF, NPT / CCF and P25 / CCF, respectively. The main intermediates produced by the photo-electrocatalytic degradation of gaseous benzaldehyde are benzene, 1,3-hexadiene-5-yne, and small amounts of 3,3,5-trimethylcyclohexene, 2,3-dimethyl- Heptadiene, 3-methyl-3-cyclohexen-1-ol and the like. Based on the results of GC / MS analysis, the degradation mechanism of benzaldehyde in gas phase was further proposed.