Nam Dae-Hyun, Shekhah Osama, Lee Geonhui, Mallick Arijit, Jiang Hao, Li Fengwang, Chen Bin, Wicks Joshua, Eddaoudi Mohamed, Sargent Edward H
Department of Electrical and Computer Engineering, University of Toronto, 10 King's College Road, Toronto, Ontario M5S 3G4, Canada.
Division of Physical Sciences and Engineering, Advanced Membranes and Porous Materials Center, Functional Materials Design, Discovery and Development Research Group (FMD3), King Abdullah University of Science and Technology (KAUST), Thuwal 23955-6900, Kingdom of Saudi Arabia.
J Am Chem Soc. 2020 Dec 23;142(51):21513-21521. doi: 10.1021/jacs.0c10774. Epub 2020 Dec 15.
In the electrochemical CO reduction reaction (CORR), control over the binding of intermediates is key for tuning product selectivity and catalytic activity. Here we report the use of reticular chemistry to control the binding of CORR intermediates on metal catalysts encapsulated inside metal-organic frameworks (MOFs), thereby allowing us to improve CORR electrocatalysis. By varying systematically both the organic linker and the metal node in a face-centered cubic () MOF, we tune the adsorption of CO, pore openness, and Lewis acidity of the MOFs. Using X-ray absorption spectroscopy (XAS) and Raman spectroscopy, we reveal that the MOFs are stable under operating conditions and that this tuning plays the role of optimizing the *CO binding mode on the surface of Ag nanoparticles incorporated inside the MOFs with the increase of local CO concentration. As a result, we improve the CO selectivity from 74% for Ag/Zr--MOF-1,4-benzenedicarboxylic acid (BDC) to 94% for Ag/Zr--MOF-1,4-naphthalenedicarboxylic acid (NDC). The work offers a further avenue to utilize MOFs in the pursuit of materials design for CORR.
在电化学CO还原反应（CORR）中，控制中间体的吸附对于调节产物选择性和催化活性至关重要。在此，我们报道利用网状化学来控制CORR中间体在封装于金属有机框架（MOF）内的金属催化剂上的吸附，从而改进CORR电催化性能。通过系统地改变面心立方（ ）MOF中的有机连接体和金属节点，我们调节了MOF对CO的吸附、孔开放性和路易斯酸度。利用X射线吸收光谱（XAS）和拉曼光谱，我们揭示了MOF在操作条件下是稳定的，并且这种调节起到了随着局部CO浓度的增加优化MOF内所包含的Ag纳米颗粒表面上*CO吸附模式的作用。结果，我们将CO选择性从Ag/Zr- -MOF-对苯二甲酸（BDC）的74%提高到了Ag/Zr- -MOF-萘二甲酸（NDC）的94%。这项工作为在追求CORR材料设计中利用MOF提供了一条新途径。
