Dynamic proton migration in dual linkage-engineered D-π-A system for photosynthesis H_(2)O_(2) generation  

双连接工程D-π-A体系中光合作用生成H_(2)O_(2)的动态质子迁移

作　　者：Zhihan Yu Dainan Zhang Chenbing Ai Jianjun Zhang Quanjun Xiang 余治晗;张岱南;艾陈斌;张建军;向全军(电子科技大学电子科学与工程学院,电子薄膜与集成器件国家重点实验室,四川成都610054;中国地质大学材料科学与化学学院,太阳能燃料实验室,湖北武汉430078)

机构地区：[1]State Key Laboratory of Electronic Thin Film and Integrated Devices,School of Electronic Science and Engineering,University of Electronic Science and Technology of China,Chengdu 610054,Sichuan,China [2]Laboratory of Solar Fuel,Faculty of Materials Science and Chemistry,China University of Geosciences,Wuhan 430078,Hubei,China

出　　处：《Chinese Journal of Catalysis》2024年第12期71-81,共11页催化学报(英文)

基　　金：国家自然科学基金(22272019);四川省科技项目(2024NSFSC0227,2022NSFSC1213,2023NSFSC106).

摘　　要：Accelerated charge migration and proton transfer to the reaction site are critical factors for improving photocatalytic efficiency.However,realizing both simultaneously is challenging because of the sluggish water(proton source)oxidation kinetics and interdependent redox reactions.Herein,we design an imide and hydrogen bond to connect carbon nitride ports of the D-π-A system with the dual-engineered linkages.The system uses an acetylene functional group and an imidazole ring as spatially separated water oxidation and oxygen reduction reaction(ORR)catalytic centers for photogenerated charge separation,respectively.The imine bond is a bridge grafted to the oxidation site to act as a hydrogen proton trap,and the hydrogen bond formed between reduction site and carbon nitride is used as the channel for instantaneous proton delivery to the reduction center.In situ characterization confirms that the linking sites protonation optimizes the pathway of ORR to H_(2)O_(2) and facilitates the*OOH intermediates generated.It is concluded that proton transport plays a critical role in optimizing photocatalytic H_(2)O_(2) production.Our work provides a strategy to improve dynamic proton transfer mechanisms.过氧化氢(H_(2)O_(2))通过水氧化反应(WOR)和氧还原反应(ORR)进行人工光合作用的研究备受关注.加速电荷迁移和质子向反应位点的转移是提高光催化效率的关键因素.然而,动力学缓慢的水氧化半反应需要为动力学更快的氧还原提供质子源,这严重限制了光催化反应的整体效率.因此,从实验方面协调光催化整体水分解仍极具挑战,这对质子从WOR位点到ORR位点的传质效率和电子在ORR位点的聚集都有很高的要求.本文展示了一种通过在嫁接氧化还原位点体系中使用加速质子迁移的嫁接端口,从而提高光生电荷载流子和质子转移速率的方法.在该方法中离子液体1,3-二甲基咪唑四氟硼酸盐(IL)和4-乙炔苯甲醛(ABE)分别嫁接在π共轭氮化碳上充当ORR位点和WOR位点,用于光催化生成H_(2)O_(2).其中,亚胺键作为调节WOR位点与氮化碳之间质子传递的良好接枝桥梁,其具有较强的电负性,易于质子化,能够快速捕获质子.离子液体与氮化碳的sp 2 N之间形成氢键,为质子跃迁到ORR位点提供了有效的通道.原位红外表征测试结果表明,ORR位点和接枝桥梁的协同作用促进了氧和质子的还原反应,加快了*OOH中间体的形成.超快飞秒光谱结果表明,氧化还原位点可以加快光生电子-空穴对的解离.飞秒光谱的寿命分析结果表明,IL作为电子捕获剂加大了对电子的吸引作用,同时ABE作为空穴捕获剂进一步延长了光生电子-空穴对的重组途径.合成的光催化剂能够偶联WOR和ORR,促进空气和水中H_(2)O_(2)的光催化合成.在实际空气氛围下,光催化剂表现出较好的O_(2)利用率,直接以空气为氧源生成H_(2)O_(2),H_(2)O_(2)的合成速率与纯O_(2)几乎相同.在可见光照射下,实现了稳定且较好的光催化产H_(2)O_(2)性能,远优于原始的g-C_(3)N_(4)光催化剂.综上,本文证明了在具有接枝氧化还原位点的体系中,设计用于促进质子迁移的端口可以�

关 键 词：Graphite carbon nitride Proton migration Redox site H_(2)O_(2)photosynthesis 

分 类 号：O57[理学—粒子物理与原子核物理]