Wang Changli, Lv Zunhang, Liu Yarong, Dai Lu, Liu Rui, Sun Caiting, Liu Weiyi, Feng Xiao, Yang Wenxiu, Wang Bo
Key Laboratory of Cluster Science Ministry of Education, Beijing Key Laboratory of Photoelectronic/Electrophotonic Conversion Materials, Advanced Technology Research Institute (Jinan), Advanced Research Institute of Multidisciplinary Science, School of Materials Science and Engineering, School of Chemistry and Chemical Engineering, Beijing Institute of Technology, No. 5, South Street, Zhongguancun, Haidian District, Beijing, 100081, China.
Angew Chem Int Ed Engl. 2024 Oct 24;63(44):e202411216. doi: 10.1002/anie.202411216. Epub 2024 Sep 12.
2D functional porous frameworks offer a platform for studying the structure-activity relationships during electrocatalytic CO reduction reaction (CORR). Yet challenges still exist to breakthrough key limitations on site configuration (typical M-O or M-N units) and product selectivity (common CO-to-CO conversion). Herein, a novel 2D metal-organic framework (MOF) with planar asymmetric N/O mixed coordinated Cu-NO unit is constructed, labeled as BIT-119. When applied to CORR, BIT-119 could reach a CO-to-C conversion with C partial current density ranging from 36.9 to 165.0 mA cm in flow cell. Compared to the typical symmetric Cu-O units, asymmetric Cu-NO units lead to the re-distribution of local electron structure, regulating the adsorption strength of several key adsorbates and the following catalytic selectivity. From experimental and theoretical analyses, Cu-NO sites could simultaneously couple the atop-type (on Cu site) and bridge-type (on Cu-N site) adsorption of *C species to reach the CO-to-C conversion. This work broadens the feasible C-C coupling mechanism on 2D functional porous frameworks.
二维功能多孔框架为研究电催化CO还原反应（CORR）过程中的构效关系提供了一个平台。然而，在突破位点构型（典型的M-O或M-N单元）和产物选择性（常见的CO到CO转化）的关键限制方面仍然存在挑战。在此，构建了一种具有平面不对称N/O混合配位Cu-NO单元的新型二维金属有机框架（MOF），标记为BIT-119。当应用于CORR时，BIT-119在流动池中可以实现CO到C的转化，C的分电流密度范围为36.9至165.0 mA cm。与典型的对称Cu-O单元相比，不对称的Cu-NO单元导致局部电子结构的重新分布，调节了几种关键吸附质的吸附强度以及随后的催化选择性。通过实验和理论分析，Cu-NO位点可以同时耦合*C物种的顶位型（在Cu位点上）和桥位型（在Cu-N位点上）吸附，以实现CO到C的转化。这项工作拓宽了二维功能多孔框架上可行的C-C偶联机制。
