Open AccessSuppressing the liquid product crossover in electrochemical CO 2 reduction
Author(s) -
Wang Ning,
Miao Rui Kai,
Lee Geonhui,
Vomiero Alberto,
Sinton David,
Ip Alexander H.,
Liang Hongyan,
Sargent Edward H.
Publication year - 2021
Publication title -
smartmat
Language(s) - English
Resource type - Journals
ISSN - 2688-819X
DOI - 10.1002/smm2.1018
Subject(s) - electrochemistry , electrolyte , formate , faraday efficiency , commodity chemicals , membrane , liquid fuel , chemical engineering , chemistry , materials science , process engineering , electrode , organic chemistry , catalysis , engineering , combustion , biochemistry
Coupling electrochemical CO 2 reduction (CO 2 R) with a renewable energy source to create high‐value fuels and chemicals is a promising strategy in moving toward a sustainable global energy economy. CO 2 R liquid products, such as formate, acetate, ethanol, and propanol, offer high volumetric energy density and are more easily stored and transported than their gaseous counterparts. However, a significant amount (~30%) of liquid products from electrochemical CO 2 R in a flow cell reactor cross the ion exchange membrane, leading to the substantial loss of system‐level Faradaic efficiency. This severe crossover of the liquid product has—until now—received limited attention. Here, we review promising methods to suppress liquid product crossover, including the use of bipolar membranes, solid‐state electrolytes, and cation‐exchange membranes‐based acidic CO 2 R systems. We then outline the remaining challenges and future prospects for the production of concentrated liquid products from CO 2 .