Highly Efficient Bipolar Membrane CO2 Electrolysis

CO2 reduction reaction (CO2RR) is a promising way to convert CO2 into value-added products. Membrane-based gas-phase CO2RR offers several advantages like high selectivity and energy efficiency. However, high product crossover and poor CO2 utilization in anion exchange membranes (AEMs) prevents the utilization of AEMs for CO2RR. The acidic environment of the cation exchange membrane can negatively influence the CO2 reduction reaction (CO2RR) activity by favoring the competing hydrogen evolution reaction (HER). Hence, it is necessary to manipulate the local pH environment of the electrodes to yield maximum productivity. Bipolar membranes (BPMs) with a cation exchange layer (CEL) and an anion exchange layer (AEL) help in maintaining different local pH environments at each electrode. Now, a bipolar membrane fabrication with a weak-acid cation exchange layer removes the possibility of competing HER without affecting CO2RR.

Automated summary

CO2 reduction reaction (CO2RR) is a promising method to convert CO2 into value-added products, and membrane-based gas-phase CO2RR offers advantages like high selectivity and energy efficiency. However, poor CO2 utilization and high product crossover in anion exchange membranes (AEMs) hinder their use in CO2RR, requiring the manipulation of local pH environments with bipolar membranes (BPMs) to increase productivity.