Ta/Al-Fe2O3薄膜电极的制备及其光电催化降解亚甲基蓝性能

采用简单的涂滴法制备出新型的Al、Ta 共掺杂的三元铁氧化物(Ta/Al-Fe₂O₃)可见光响应型光催化薄膜. 运用X射线光电子能谱(XPS)和紫外-可见(UV-Vis)光谱等手段对其进行了表征, 考察了其光电化学性能, 并研究了复合电极光电催化降解亚甲基蓝(MB)废水的反应性能. 由表面谱学分析可知, Ta 和Al 成功掺入Fe₂O₃中, Ta 会改变催化剂表面Al 和O的化学环境. 在可见光照射下的光电催化(PEC)反应中, Ta/Al-Fe₂O₃降解MB的反应速率约为Al-Fe₂O₃的2 倍, 光电催化共作用的效果优于单纯光催化作用(PC)和电催化(EC)作用的效果.结果表明, Ta掺杂有利于提高Ta/Al-Fe₂O₃薄膜的光电催化活性.

Synthesis of Ta/Al-Fe2O3 Film Electrode and Its Photoelectrocatalytic Performance in Methylene Blue Degradation

A novel visible-light-responsive photoanode (Ta/Al-Fe₂O₃) was fabricated by co-doping Ta and Al into iron oxide. The properties of the prepared electrodes were examined using X- ray photoelectron spectroscopy (XPS) and ultraviolet-visible (UV-Vis) diffuse reflectance spectroscopy. XPS analysis suggested that the surface chemical environments of Al and O were significantly affected by Ta doping. Photoelectrochemical (PEC), electrocatalytic (EC), and photocatalytic (PC) degradations of methylene blue (MB) were performed using Ta/Al-Fe₂O₃ and Al-Fe₂O₃ electrodes as the photoanodes. The results indicated that synergetic effects in PEC enhanced the MB degradation efficiency compared with the individual PC or EC processes. The estimated rate constant for MB degradation on Ta/Al-Fe₂O₃ was about twice that on Al-Fe₂O₃ under visible-light irradiation in the PEC process. The greatly improved visible-light activity and film stability indicated that Ta doping was an efficient way to improve the PEC activity of Ta/Al-Fe₂O₃ films.