Ru负载促进GeZnNO固溶体光解水反应的机理研究

Enhancement on photocatalytic water splitting by Ru loading on GeZnNO solid solution

光催化水分解生成氢气和氧气是解决环境污染和能源危机的方法之一,但当前对光解水的反应机理研究较少.本文通过进一步研究反应路径,以期为合成高效率光解水反应光催化剂提供新思路.采用固态合成法制备了GeZnNO可见光催化剂,并对部分催化剂进行RuO_(2)改性.同时,通过XRD、BET、UV-vis-DRS、PL等方法对催化剂进行表征.在整个光催化水分解体系中加入可能的中间产物H_(2)O_(2),分别观察•OH和O_(2)的变化,初步证明H_(2)O_(2)是水分解中间产物,并提出相应水分解反应机理.通过在整个光催化水分解体系中加入Fe^(3+),观察•OH和O_(2)的变化,进一步验证了前面的推测.最终结果表明,H_(2)O_(2)是光催化水分解反应体系中氧气生成的中间产物,对整个水分解起着重要作用.同时发现,RuO_(2)助催化剂不仅具有析氢位点的作用,还能够催化H_(2)O_(2)分解产生O_(2),促进水分解的进行.该研究结果可为光催化水分解性能的进一步提高提供理论参考.

Photocatalytic water splitting is one of the promising ways to solve environmental pollution and energy crisis.However,there is little research on the reaction mechanism and reaction path of photolysis of water at present.In this study,GeZnNO catalysts were prepared by solid-state synthesis,some of which were modified with RuO_(2).The catalysts were characterized by XRD,BET,UV-vis-DRS,PL and other methods.With the addition of the possible intermediate product H_(2)O_(2) to the entire photocatalytic water splitting system,and the observation on changes of•OH and O_(2) respectively,it was preliminarily proved that H_(2)O_(2) was an intermediate product of water splitting,which were further verified by the addition of Fe^(3+).The results show that H_(2)O_(2) is an intermediate product of oxygen generated in the photocatalytic water splitting reaction system and plays an important role in the entire water splitting.At the same time,it was found that the RuO_(2) promoter could not only function as a hydrogen evolution site,but also catalyze the decomposition of H_(2)O_(2) to produce O_(2).The research results can provide a theoretical reference for the further improvement of photocatalytic water splitting performance.