In the electrochemical CO2 reduction reaction (CO2RR), 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 CO2RR intermediates on metal catalysts encapsulated inside metal–organic frameworks (MOFs), thereby allowing us to improve CO2RR electrocatalysis. By varying systematically both the organic linker and the metal node in a face-centered cubic (fcu) MOF, we tune the adsorption of CO2, pore openness, and Lewis acidity of the MOFs. Using operando X-ray absorption spectroscopy (XAS) and in situ 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 CO2 concentration. As a result, we improve the CO selectivity from 74% for Ag/Zr-fcu-MOF-1,4-benzenedicarboxylic acid (BDC) to 94% for Ag/Zr-fcu-MOF-1,4-naphthalenedicarboxylic acid (NDC). The work offers a further avenue to utilize MOFs in the pursuit of materials design for CO2RR.
Bibliographical noteKAUST Repository Item: Exported on 2020-12-17
Acknowledgements: This publication is based upon work supported by the King Abdullah University of Science and Technology (KAUST) Office of Sponsored Research (OSR) under Award No. OSR2018-CPF-3665-03. This research used synchrotron resources of the Advanced Photon Source (APS), an Office of Science User Facility operated for the US Department of Energy Office of Science by Argonne National Laboratory and was supported by the US Department of Energy under Contract No. DEAC02-06CH11357 and the Canadian Light Source and its funding partners. The authors thank Dr. T. P. Wu, Dr. Y. Z. Finfrock, Dr. G. Sterbinsky, and Dr. L. Ma for technical support at 9-BM beamline of APS. The authors acknowledge the use of facilities within CFI-funded Ontario Centre for the Characterization of Advanced Materials at the University of Toronto. This research was supported by the program of Carbon to X technology development for production of useful
substances (2020M3H7A1098376), through the National Research Foundation of Korea (NRF), funded by the Korean government (Ministry of Science and ICT (MSIT)).