CO electrolysers with 51% energy efficiency towards C2+ using porous separators
Source abstract
Abstract
Electrochemical CO2 reduction can generate multi-carbon (C2+) products via a CO2-to-CO cascade followed by CO reduction (COR). However, COR energy efficiency remains below 40% due to sluggish ion transport within charge-selective membranes. Here we introduce an uncharged porous separator that enables facile transport of both ion types, reducing ohmic resistance and superconcentrating cations at the catalyst surface-lowering COR voltage by 150 mV at 200 mA cm-2. In previous electrolyser designs, porous separators were limited by cathode-to-anode H2 crossover; the low diffusivity of C2H4 and CO in water allows a separator three times thinner and 1.6 times more porous, markedly reducing overpotential. Operating at elevated temperatures with a nickel-iron-based anode further lowers voltage by 330 mV, leading to a full-cell voltage of 1.95 V at 200 mA cm-2 and an energy efficiency of 51% to C2+ products sustained over 250 h. The system also achieves a CO single-pass conversion of 97% and a C2H4 concentration of 87 wt% in the product gas stream.
Source: openaire · Quality: candidate unverified · Source record ↗
Research context
OpenAlex topics: CO2 Reduction Techniques and Catalysts · Catalytic Processes in Materials Science · Carbon dioxide utilization in catalysis
SciVX discovery tags are terminology-based. OpenAlex topics are source-provided classifications.
References (44)
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