Maximizing Ag Utilization in High-Rate CO2 Electrochemical Reduction with a Coordination Polymer-Mediated Gas Diffusion Electrode

by R. Wang, H. Haspel, A. Pustovarenko, A. Dikhtiarenko, A. Russkikh, G. Shterk, D. Osadchii, S. Ould-Chikh, M. Ma, W. A. Smith, K. Takanabe, F. Kapteijn, J. Gascon
Year: 2019

Bibliography

R. Wang, H. Haspel, A. Pustovarenko, A. Dikhtiarenko, A. Russkikh, G. Shterk, D. Osadchii, S. Ould-Chikh, M. Ma, W. A. Smith, K. Takanabe, F. Kapteijn and J. Gascon. ACS Energy Lett. 4 (2019) 2024−2031. Maximizing Ag Utilization in High Rate CO2 Electrochemical Reduction with a Coordination Polymer Mediated Gas Diffusion Electrode

Abstract

​We report the preparation and electrocatalytic performance of silver-containing gas diffusion electrodes (GDEs) derived from a silver coordination polymer (Ag-CP). Layer-by-layer growth of the Ag-CP onto porous supports was applied to control Ag loading. Subsequent electro-decomposition of the Ag-CP resulted in highly selective and efficient CO2-to-CO GDEs in aqueous CO2 electroreduction. Afterward, the metal–organic framework (MOF)-mediated approach was transferred to a gas-fed flow electrolyzer for high current density tests. The in situ formed GDE, with a low silver loading of 0.2 mg cm–2, showed a peak performance of jCO ≈ 385 mA cm–2 at around −1.0 V vs RHE and stable operation with high FECO (>96%) at jTotal = 300 mA cm–2 over a 4 h run. These results demonstrate that the MOF-mediated approach offers a facile route for manufacturing uniformly dispersed Ag catalysts for CO2 electrochemical reduction by eliminating ill-defined deposition steps (drop-casting, etc.) while allowing control of the catalyst structure through self-assembly.​

Keywords

CO2 conversion Electrocatalysis Metal Organic Framework Gas diffusion electrode