导电玻璃负载Fe_2O_3/ZnO复合光电极的制备及光电催化性能

Preparation and Photoelectrocatalytic Performance of Fe_2O_3/ZnO Composite Electrode Loading on Conductive Glass

以聚乙烯吡咯烷酮(PVP)为纤维骨架,乙醇为溶剂,乙酸锌[Zn(CH_3COO)_2·2H_2O]和三乙酰丙酮铁(C_(15)H_(21)O_6Fe)为原料,利用静电纺丝技术结合溶胶-凝胶法制备前驱体纤维,经焙烧后得到不同摩尔比的FTO导电玻璃负载Fe_2O_3/ZnO复合光电极(Fe_2O_3/ZnO/FTO).利用热重-差热分析仪(TG-DTA)、X射线衍射仪(XRD)、扫描电子显微镜(SEM)和X射线光电子能谱仪(XPS)等对材料进行了表征,以亚甲基蓝(MB)为目标降解物,探讨了复合材料的光电催化活性.结果表明,Fe_2O_3与ZnO的复合能够有效构建p-n异质结,利于光生电子和空穴的分离,其光电催化性能较纯ZnO/FTO和Fe_2O_3/FTO均有明显提高;不同n(Fe)/n(Zn)的复合光电极表现出了不同的光电催化活性,在相同催化时间内,当n(Fe)/n(Zn)=1∶1时,Fe_2O_3/ZnO/FTO对MB催化活性最佳,MB的降解率达到97%.

Using polyvinylpyrrolidone（ PVP） and ethanol as fiber skeleton and solvent,respectively,Fe2O3/ZnO precursor fibers were prepared by sol-gel method combined with electrospinning technique with zinc acetate [Zn（CH3COO）2·2 H2O]and three iron acetylacetonate（ C（15）H（21）O6Fe） as raw materials. Fe2O3/ZnO/FTO composite photoelectrodes with different Fe/Zn molar ratios were obtained by calcination. The morphologies and chemical components were characterized by thermogravimetry-differential thermal analysis（ TG-DTA）,X-ray diffraction（ XRD）,scanning electron microscopy（ SEM）,X-ray photoelectron spectroscopy（ XPS）,and so on. The photoelectrocatalytic performance of the obtained sample was tested by the degradation of methylene blue（ MB） solution. The results indicate that the p-n heterojunctions between ZnO and Fe2O3 are beneficial for separation of photogenerated electrons and holes,resulting in Fe2O3/ZnO/FTO with high catalytic activity in comparsion with ZnO/FTO and Fe2O3/FTO. The composite photoelectrodes with different Fe/Zn molar ratios exhibit different photoelectrocatalytic activity. When n（ Fe）/n（ Zn） is 1 ∶ 1,the catalytic activity of Fe2O3/ZnO/FTO is the optimal,the degradation rate of MB is 97% after 140 min.