主客体超分子应用于光催化水分解体系的研究

Development of artificial photosynthesis, utilization of sunlight to split water is an ideal way to convert solar energy into chemical fuels to solve the energy crisis and environmental pollution. The host−guest interaction is essential to facilitate the electron transfer from catalyst to sensitizer, indicating that the noncovalent incorporation of sensitizer and catalyst is an appealing approach for photocatalytic water oxidation. However，the basic aim for aritificial synthesis is overall water splitting. Based on the host−guest interaction, the main contents are as follows: 1) The coupling chromophore-catalyst assembly with proton reduction reaction to construct a Z-scheme photocatalytic water spltting system on molecular level. 2) A strategy for spontaneously assembling chromophore-catalyst on semiconductor based on the host-guest interaction is straightforward, which offers considerable flexibility for the selection of a water oxidation catalyst. It is a novel approach for the modification of molecular catalysts on the electrodes. Based on this method, a dye-sensitized photoelectrochemical cell will be assembled with high catalytic activity and based on cheap catalysts. The related research of this project will provide a new avenue for developing efficient overall water splitting reaction.

人工模拟光合作用，利用太阳能分解水是实现光能转化成化学能，有效解决当今社会能源危机和环境污染问题的一个理想选择。通过主客相互作用方式,构建光敏剂催化剂自组装超分子，能显著加快水氧化反应过程中的电荷传递效率，从而提高光催化水氧化活性。而实现水的全分解是人工光合作用的根本目的。基于主客相互作用方式，本项目将开展的主要内容如下：（1）主客超分子体与质子还原半反应有机耦合，构建分子水平Z-scheme光催化水分解体系；（2）主客相互作用的方法构建新型光电极，便于催化剂筛选，为分子催化剂修饰在电极上开辟了一条新的途径。基于该方法，筛选非贵金属催化剂，组装高催化活性、基于廉价催化剂修饰的染料敏化光电分解水电池。本项目的研究将为开发高效的水全分解反应提供一种新的思路。

电催化水分解产氢是一种理想的能源解决方案。在整个水分解过程中，水氧化半反应因涉及多个质子和电子转移，是整个反应的瓶颈。因此，发展基于廉价材料的具有高催化活性的水氧化反应催化剂至关重要。以往催化剂是直接生长在金属泡沫基底上或通过粘结剂负载，电催化水氧化性能受限。本项目以金属泡沫为基底，首先在其表面生长金属氢氧化物前驱体，然后以其作为牺牲模板制备基于廉价金属中心的MOF材料电极并研究其催化水氧化反应性能。电催化水氧化反应测试表明模板法所制得的催化剂具有较高的催化活性和稳定性。通过考察电化学活性表面积和电化学阻抗，阐明了牺牲模板法所制备的电极较其它方法所制备的电极活性高的原因。同时，对长时间电解后电极表面的材料进行了结构分析，探索出了催化过程中催化活性物种的变化。本申请为制备基于廉价金属的具有高催化活性的电催化储能材料提供了一条新思路。