Synergistic electroreduction of CO2 to C1-C3 gas products in a pressure-tolerant MEA system

Electrochemical reduction of carbon dioxide offers a sustainable route to reduce CO 2 to combat climate change and advance renewable energy use. However, challenges such as high energy demand and unsatisfactory selective production of higher hydrocarbons (C 2+ ) hinder its practical implementation. This work investigates the effects of operating conditions on the performance of CO 2 electroreduction, based on an optimized zero-gap electrolyzer design and a high-pressure reaction setup. The results show that moderate temperatures can increase energy efficiency and selectivity, with Faradaic efficiencies over 40 % for C 1 –C 3 gas products. High-pressure environments exceeding 10 bar can improve the availability and mass transport of CO 2 , and suitable proportions of syngas for subsequent reuse can be generated in this harsh environment. Tandem-layer catalysts can enhance CO generation, highlighting the need for precise control of catalyst interactions. In addition, lower neutral electrolyte concentrations favor the formation of C 2+ products but consume higher energy compared to alkaline environments. These findings provide insights and strategies for optimizing CO 2 electrolysis systems, aiding the development of efficient and scalable technologies for practical applications. • C 1 –C 3 gas products form at 1.2 A with 40 % FE for 3 h. • Manage high pressure CO 2 RR in a modified zero-gap electrolyzer. • A high current of 3 A is available at 3 V cell voltage. • Electrolyte type/concentration affects the formation of C 2+ gas. • Both catalysts and operation engineering are critical for CO 2 RR.