TiO2及负载Fe(Ⅲ)可见光催化H2O2降解扑草净的协同效应

以TiO2P25(TIO-P25)及Fe(NO3)3为前驱物制备TiO2负载Fe3+多相催化剂Fe/TIO-P25,研究Fe/TIO-P25可见光催化H2O2降解扑草净的协同效应.XRD、XPS、EDS及SEM结果表明,Fe元素以Fe2O3形式高度分散于TiO2表面,负载量约1.5%(wt%),未对TIO-P25的粒径及形貌产生明显影响,Fe/TIO-P25的粒径约20~40nm;光催化结果表明,Fe/TIO-P25能可见光催化H2O2降解扑草净,反应30min降解率达100%,远大于TIO-P25的催化活性,负载Fe与TIO-P25之间存在明显的协同效应;通过对反应体系的荧光光谱分析显示,扑草净的降解涉及较单纯羟基自由基(·OH)过程更为复杂的反应机理.

The synergistic effects of prometryn degradation with H2O2 photocatalyzed by TiO2 and loading Fe3+ under visible irradiation

A heterogeneous catalyst with TiO2 as carrier(Fe/TIO-P25) was prepared using TiO2P25(TIO-P25) and Fe(NO3)3 as precursors, its synergistic effects with H2O2 assistance were also studied using prometryn as model pollutant. XRD, XPS, EDS and SEM analytical results indicated that iron element was highly dispersed on the surface of TIO-P25 with the form of Fe2O3, its loading was about 1.5% (wt%), and had not evident influence on the particle size and microscopic morphology of TIO-P25, the particle size of Fe/TIO-P25 was about 20~40nm. The photocatalytic results indicated that prometryn could be degraded by Fe/TIO-P25 with H2O2 and visible light assistance, the degradation ratio could be 100% after 30minutes reaction, and the degradation efficiency was far more than TIO-P25, showing evident synergistic effects between immobilized iron and TIO-P25. Fluorescence spectrum analysis indicated that the reaction process was not limited to the generation of hydroxyl free radicals (·OH) in the system.