宽光谱响应光/电化学生成光生电子和光生空穴协同处理难降解有机污染物

The photogenerated hole and hydroxyl radicals with high activity is one of most promising methods to decompose the new type pollutant such as refractory organic pollutants。 Effective production of hydroxyl becomes one of the most important research topics for environmental chemistry. In photo/electro catalytic process, the photogenerated hole and the hydroxyle radical from photoanode are highly active for decomposition of organic pollutant, while the photogenerated electron is usually transfer to counter electrode for hydrogen evolution. In this proposal, a Fenton-like hybrid electrode is designed to connect with the photoanode in photoelectrochemical cells. The photogenerated electron would transfer to the Fenton-like hybrid electrode’s functional nanocarbon electrode to reduce the O2 to generate the H2O2, and the H2O2 would be catalyzed to form hydroxyle radical by the hetergenous Fenton-like catalysts on the Fenton-like hybrid electrode. To form light driven bias potential and more efficiently ultlization of solar energy, a band gap tunable perovskite photovoltaic device is designed to couple with the photoanode and the Fenton-like hybrid electrode. In all, the solar energy would be converted to produce the highly active photogenerated hole and hydroxyle radical with enhanced efficiency based on this wider solar spectrum active photo/electrochemical deivce.

具有强烈反应活性的光生空穴和羟基自由基是降解各种新型难降解污染物的有效技术手段之一，有效的通过光激发的光生空穴和生成羟基自由基进行污染物处理是环境化学的重要研究方向。在光电化学催化中，光阳极生成的光生空穴和羟基自由基可有效降解有机污染物，但是其中的光生电子一般被用于产氢反应。本项目计划用一个类芬顿复合电极作为光电化学电池中的对电极，该类芬顿复合电极可以利用其纳米功能碳电极将光生电子还原O2制得H2O2，同时利用类芬顿复合电极上的异相类芬顿催化剂将H2O2转化为羟基自由基。通过这个组合使得光生电荷，在合适偏压下都可以用于生成羟基自由基。此外，我们计划将能隙可调的钙钛矿太阳能电池和光阳极串联，利用钙钛矿太阳能电池来产生额外的电压来减少额外偏压乃至实现自偏压。通过组合串联光电阳极，钙钛矿太阳能电池以及类芬顿复合电极，太阳光将能够更有效被用于生成羟基自由基进行难降解环境污染物的处理。

为充分有效利用太阳能光谱，本项目中利用带隙可调的钙钛矿太阳能电池来作为光生偏压源，瞄准了具有优异化学稳定性的无机钙钛矿作为研究对象。基于表面端基化和提出新型β型无机钙钛矿等创新思路，引领了无机钙钛矿太阳能电池的发展，多次打破无机钙钛矿太阳能电池效率记录。为了有效实现光电极有效的生长光生载流子进行光电催化，本项目瞄准了BiVO4和Si等光电极，基于表面修饰等策略大幅提高了光电极的催化效率。为了提高高活性自由基的活化，提出了基于Ni和Mn这些低毒性的高效类芬顿催化剂，有效的实现了芬顿活化效率。这些研究提高了光电催化的效率和高级氧化的应用范围。