Acid–Base Interaction Enhancing Oxygen Tolerance in Electrocatalytic Carbon Dioxide Reduction
Pengsong Li, Lu Xu, Zishan Wu, Yueshen Wu, Richard Malpass‐Evans, Neil B. McKeown, Xiaoming Sun, Hailiang Wang
Abstract
Abstract Hybrid electrodes with improved O 2 tolerance and capability of CO 2 conversion into liquid products in the presence of O 2 are presented. Aniline molecules are introduced into the pore structure of a polymer of intrinsic microporosity to expand its gas separation functionality beyond pure physical sieving. The chemical interaction between the acidic CO 2 molecule and the basic amino group of aniline renders enhanced CO 2 separation from O 2 . Loaded with a cobalt phthalocyanine‐based cathode catalyst, the hybrid electrode achieves a CO Faradaic efficiency of 71 % with 10 % O 2 in the CO 2 feed gas. The electrode can still produce CO at an O 2 /CO 2 ratio as high as 9:1. Switching to a Sn‐based catalyst, for the first time O 2 ‐tolerant CO 2 electroreduction to liquid products is realized, generating formate with nearly 100 % selectivity and a current density of 56.7 mA cm −2 in the presence of 5 % O 2 .