量子点敏化型光电极的异质界面设计及催化污水产氢研究

For the sustainable development of wastewater treatment, a novel quantum dots sensitized heterostructured photoelectrochemical system will be designed. The potential of photoelectrodes for simultaneous wastewater treatment and energy production will be investigated. Firstly, several environmental-friendly and low-cost photoelectric functional materials will be explored, including multimetal sulfide nanocrystals, carbon nitride quantum dots, black phosphorus quantum dots. The strategies of interfacial effect and energy level matching will be used to design high-efficiency quantum dots sensitized photoelectrodes. Secondly, by adjusting the Fermi levels of the integrated photoelectrodes, the synergistic effect between light-induced build-in electric field and external electric field will be strengthened. Therefore, the enhanced photoelectrocatalytic degradation of pollutant and production of hydrogen energy will be achieved. Finally, ultra-fast spectroscopy and time-resolved photoconductivity will be used to investigate the light-induced active species, as well as the reaction kinetics. The synergistic photoelectrocatalytic mechanism will be established, according to the formation, transfer and recombination processes of charge carriers. This research will provide some theoretical basis for the exploration of green wastewater treatment techniques, which meet the requirements of sustainable and harmonious development.

本研究面向污水处理过程可持续发展的技术需求，基于异质界面设计开发新型量子点敏化型光电催化体系，深入挖掘光电极在污水处理同时进行氢能源生产中的应用潜力。首先，探索开发环境友好性、低成本的多元金属硫化物纳米晶、氮化碳量子点、黑磷量子点等新型光电功能材料，通过异质结构设计和能级匹配作用构筑新型量子点敏化光电极，以实现宽光谱激发下量子点独特的多激子效应在高效光电催化反应中的应用。其次，在双光电极的整体结构设计和界面费米能级调节的基础上，强化光生内建电场和外置电场间的协同作用，最终实现光电氧化降解污染物和光电催化还原制氢反应的互为促进。再次，通过超快光谱、瞬态光电等技术对活性物种种类及其反应动力学进行研究。基于载流子的转移和复合过程建立协同光电催化机理，从而为探索符合绿色可持续发展要求的污水处理新技术提供理论参考。

光电催化旨在通过外加电场作用实现电荷的有效分离，在协同氧化处理水中污染物的反应中具有重要应用前景。本项目针对光电催化剂光吸收能力不足、载流子复合几率高、活性物种微界面生成机制不明等关键问题，系统考察了催化剂晶面工程、氢键调控、界面缺陷、异质复合、量子点敏化等手段对微界面电荷分离和催化效率的影响。研究表明，多相催化界面缺陷的形成、分布和重构对光生载流子分离、转移以及活性物种生成具有重要影响，因此通过催化剂微观结构的选择匹配可以为强化活性物种形成和电荷转移路径的调控提供有效手段。基于以上微界面机制的指导，研究揭示出光电极微观结构与活性物种生成和污染物去除机制间的内在关系，建立了助催化剂负载和碳质复合促进界面电子传递的新方法，最终利用所开发的微流体强化传质的三维多孔电极，获得了污染物氧化去除和催化还原制氢反应效率的显著提升，为开发降解路径相匹配的高活性催化剂和催化净水同步产能系统的构建奠定了基础。项目执行期间，以第一及通讯作者在Advanced Energy Materials、Nano Energy、Applied Catalysis B-Environmental等高水平学术期刊发表SCI收录论文17篇，其中影响因子高于10的论文7篇，申请专利1项，获得专利1项。以上文章被引用300余次，研究成果得到了国内外同行的普遍认可和广泛关注。