Advances and challenges in the electroreduction of carbon dioxide in acidic electrolyte

The increasing level of atmospheric carbon dioxide (CO₂) caused by intensified human activities has exacerbated the greenhouse effect, calling for the technology of CO₂ fixation. Among the proposed technologies, electrocatalytic CO₂ reduction in acidic electrolytes has garnered significant attention for its potential in sustainable carbon utilization and renewable energy storage. This review provides a summary of recent advancements in acidic CO₂ reduction, with a focus on catalyst design strategies, the optimization of the local reaction environment, and the effect of cations. We first evaluated the performance and discussed the challenges for acidic CO₂ reduction in H-type cells, flow cells, and membrane electrode assembly. Afterward, we highlight the innovative strategies for promoting CO₂ reduction through optimizing the intrinsic activity and regulating the local environment of catalysts. The critical role of cations in enhancing CO₂ reduction selectivity is also discussed. The review concludes with an outlook on future research directions, especially the need for the design of catalysts and systems that are stable, scalable, and highly efficient.