仿生光电催化二氧化碳还原: 体系构建及电荷传输研究

Artificial photosynthesis for solar fuel production is an ideal way for solving the carbon dioxide and energy issues in China and even the world. This project will construct efficient and stable photocathodes via rational interface engineering, design and synthesize carbon dioxide adsorption-fixation-reduction enzyme-like molecular or electrocatalytic catalysts in atomic/molecular level for photoelectrocatalytic carbon dioxide reduction or hydrogenation of organic molecules to realize the selective production of chemicals. To improve the charge transfer between the photoelectrode and catalysts, redox ion couples, like NAD(P)H and its analogues, or electron transport interlayer will be introduced as an artificial charge transport chain. In addition, the mechanisms of charge transfer and carbon dioxide activation will be studied by time and space resolved spectra, photoelectrochemical characterizations and theoretical calculation etc. This proposal learns from the nature, and aims to understand the basic scientific issues in natural photosynthesis via exploring biomimetic catalysts and studying the charge transfer and reaction mechanisms in artificial photosynthesis, which will be helpful for achieving more efficient artificial solar energy conversion and utilization.

人工光合制备燃料是缓解中国乃至世界二氧化碳减排和能源问题的理想途径之一。本项目拟通过合理的表界面修饰构建高效、稳定的光阴极体系；从原子/分子级结构设计并合成二氧化碳吸附-固定-还原的复合功能仿酶分子催化剂或电催化剂，进行光电催化二氧化碳还原或有机物加氢反应，可望实现高选择性制备化学品；通过引入NAD(P)H及其类似物的氧化还原电对离子或电子传导界面层作为人工电子传输链，促进光电极和催化剂之间的电荷传输；并通过时空分辨光谱、光电表征技术和理论计算等，研究电荷传输机制和二氧化碳活化反应机理。本项目“道法自然”，旨在通过仿生催化剂的开发、人工光合电荷转移和反应机制的研究，反馈认识自然光合体系中的基础科学问题，进而实现更高效的人工太阳能转化利用。

人工光合制备燃料是缓解中国乃至世界二氧化碳减排和能源问题的理想途径之一。本项目围绕高效、稳定光电极构建、CO2还原、NADH等电荷传递链分子的转化及集成光电催化人工光合体系构建开展研究。构建了高效光电催化体系；从原子/分子级结构设计，合成了原子级分散双过渡金属-C3N4/CNT复合材料，实现高效电催化CO2还原至CO；针对电荷传输链，通过对比研究系列金属催化剂和碳材料的电催化NAD+还原性能，揭示Cu等金属催化剂表面电催化NAD+还原氢原子耦合电子转移机理；开发了仿生的过渡金属硫化物催化剂，实现高效、选择性电催化NAD+还原至1,4-NADH，模拟了自然酶催化NADPH生成功能。最终，以NADH为电荷传输媒介构建集成人工光合体系，实现光电催化NADH再生耦合有机物加氢反应或CO2还原。