【摘要】 光电化学（PEC）催化CO₂转化合成高附加值多碳化合物具有广阔的应用前景.本文将Au纳米晶修饰N掺杂Ti O₂纳米片的光阳极与Zn掺杂Cu₂O阴极相结合,构筑了高效PEC CO₂转化体系.该体系在较低外加偏压（0.5 V vs. Ag/Ag Cl）和光照条件下能够实现CO₂高效转化合成CH₃COOH,其法拉第效率高达58.1%（碳产物的选择性为91.5%）.研究人员进一步利用程序升温脱附和原位拉曼光谱发现阴极上Zn的引入能够在选择性催化CO₂转化合成CH₃COOH过程中起到关键作用:（1）优化Cu₂O局部电子结构;（2）增加表面反应活性位点;（3）促进C–C偶联中间体CH₂/*CH3_的形成.而Au纳米晶修饰N掺杂Ti O₂纳米片优异的光响应则能够为反应提供更多的光生电子,进而提高催化反应速率.这项工作不仅实现了高选择性光电化学催化CO₂向高附加值产物的转化,同时为高效PEC CO₂转化体系的设计提供了新的思路.更多还原

【Abstract】 Amidst the development of photoelectrochemical（PEC） CO₂ conversion toward practical application, the production of high-value chemicals beyond C₁ compounds under mild conditions is greatly desired yet challenging. Here, through rational PEC device design by combining Au-loaded and N-doped Ti O₂ plate nanoarray photoanode with Zn-doped Cu2 O dark cathode, efficient conversion of CO₂ to CH3 COOH has been achieved with an outstanding Faradaic efficiency up to 58.1%（91.5% carbon selectivity） at 0.5 V vs. Ag/Ag Cl. Temperature programmed desorption and in situ Raman spectra reveal that the Zn-dopant in Cu₂O plays multiple roles in selective catalytic CO₂ conversion, including local electronic structure manipulation and active site modification, which together promote the formation of intermediate*CH₂/*CH₃ for C–C coupling. Apart from that, it is also unveiled that the sufficient electron density provided by the Au-loaded and N-doped Ti O₂ plate nanoarray photoanode plays an equally important role by initiating multi-electron CO₂ reduction. This work provides fresh insights into the PEC system design to reach the multi-electron reduction reaction and facilitate the C–C coupling reaction toward high-value multicarbon(C₂₊) chemical production via CO₂ conversion.更多还原