过渡金属硫化物在高级氧化法中的研究进展

近年来,高级氧化技术(Advanced oxidation processes,AOPs)被广泛用于去除废水中的污染物,但高成本、高能耗限制了该技术的应用,开发低成本、高效、可重复利用的催化剂来降低该技术的使用成本是提高AOPs应用的有效手段。过渡金属硫化物(Transition metal sulfides,TMS)具有良好的导电性、机械稳定性和热稳定性,具有带隙可调特性的TMS可用作光催化剂。综述了TMS在AOPs中的应用,TMS可通过不饱和硫暴露金属活性位点提高Fenton法中Fe~(3+)还原为Fe~(2+)的速率,还可直接活化过硫酸盐或作光催化剂。同时介绍了TMS的改性方法,主要通过元素掺杂改性来增加活性位点,降低带隙宽度;通过TMS与金属化合物复合来提高电导率,增强催化活性;通过TMS与碳基材料复合原位生成H_2O_2,降低光生电子-空穴对的重组速率。最后,对TMS在AOPs中的发展方向进行了展望。

Research progress of transition metal sulfides in advanced oxidation processes

In recent years, advanced oxidation processes (AOPs) have been widely used to remove contaminants from wastewater, but the disadvantages of high cost and energy consumption limit the application of this technology. The development of low-cost, efficient and reusable catalysts to reduce the cost of this technology is an effective way to improve the application of AOPs. Transition metal sulfides (TMS) have good conductivity, mechanical stability and thermal stability. TMS with adjustable band gap can be used as photocatalysts. This paper reviews the applications of TMS in AOPs. TMS can increase reduction rate from Fe3+ to Fe2+ in Fenton process by exposing metallic active sites with unsaturated sulfur atoms, directly activate persulfate or peroxymonosulfate and act as photocatalysts. The modifications of TMS are also introduced, which can increase the active sites and reduce the band gap through element doping; improve the conductivity and enhance the catalytic activity through compositing with metal compounds; generate H2O2 in situ and reduce the recombination of electron hole pairs through compositing with carbonaceous-based materials. Finally, the development directions of TMS in AOPs in the future are also prospected.