School of Chemical Engineering and Technology, Tiangong University, Tianjin300387, China.
State Key Laboratory of Separation Membranes and Membrane Processes, Tiangong University, Tianjin300387, China.
Inorg Chem. 2023 Jan 16;62(2):930-941. doi: 10.1021/acs.inorgchem.2c03734. Epub 2023 Jan 6.
Electrochemical CO reduction to transportation fuels and valuable platform chemicals provides a sustainable avenue for renewable energy storage and realizes an artificially closed carbon loop. However, the rational design of highly active and selective CO reduction electrocatalysts remains a challenging task. Herein, a series of metal-organic framework (MOF)-supported flexible, self-adaptive dual-metal-site pairs (DMSPs) including 21 pairwise combinations of six transition metal single sites (MOF-808-EDTA-MM, M/M = Fe, Cu, Ni, Pd, Pt, Au) for the CO reduction reaction (CORR) were theoretically screened using density functional theory calculations. Against the competitive hydrogen evolution reaction, MOF-808-EDTA-FeFe and MOF-808-EDTA-FePt were identified as the promising CORR electrocatalysts toward C and C products. The calculated limiting potential for CO electroreduction to CH and CHOH over MOF-808-EDTA-FeFe is -0.87 V. Compared with an applied potential of -0.56 eV toward CH production over MOF-808-EDTA-FeFe, MOF-808-EDTA-FePt exhibits an even better activity for CO reduction to C products at a limiting potential of -0.35 V. The present work not only identifies promising candidates for highly selective CORR electrocatalysts leading to C and C products but also provides mechanistic insights into the dynamic nature of DMSPs for stabilizing various reaction intermediates in the CORR process.
电化学 CO 还原为运输燃料和有价值的平台化学品为可再生能源存储提供了一条可持续的途径，并实现了人为的封闭碳循环。然而，合理设计高活性和选择性的 CO 还原电催化剂仍然是一项具有挑战性的任务。在此，使用密度泛函理论计算，理论上筛选了一系列金属有机骨架（MOF）负载的柔性、自适应双金属位对（DMSP），包括六种过渡金属单原子（MOF-808-EDTA-MM，M/M = Fe、Cu、Ni、Pd、Pt、Au）的 21 种成对组合，用于 CO 还原反应（CORR）。相对于竞争的析氢反应，MOF-808-EDTA-FeFe 和 MOF-808-EDTA-FePt 被确定为有前途的 CORR 电催化剂，用于 C 和 C 产物。MOF-808-EDTA-FeFe 上 CO 电还原为 CH 和 CHOH 的计算极限电位为-0.87 V。与 MOF-808-EDTA-FeFe 上 CH 生成的应用电位-0.56 eV 相比，MOF-808-EDTA-FePt 在 -0.35 V 的极限电位下对 CO 还原为 C 产物表现出更好的活性。本工作不仅为高选择性 CORR 电催化剂的候选物，用于生成 C 和 C 产物提供了指导，而且为 DMSP 在 CORR 过程中稳定各种反应中间体的动态性质提供了机理见解。
