Advances in Electrocatalytic CO 2 Reduction Under Acidic Media: Interfacial Microenvironment, Catalyst Design, and Electrolyzers

ABSTRACT Renewable electricity‐driven electrocatalytic CO 2 reduction reaction (CO 2 RR) presents a promising route for producing value‐added chemicals, enhancing energy storage, and completing the artificial carbon cycle. Although alkaline and neutral electrolytes dominate current electrolysis systems, inevitable carbonate formation and low CO 2 utilization efficiency limit their commercial viability. In contrast, CO 2 RR in acidic electrolytes offers distinct advantages in overcoming CO 2 mass transport limitations and energy efficiency bottlenecks by avoiding carbonation side reactions and preventing solid carbonate formation. However, acidic CO 2 RR faces several challenges, including competition from the hydrogen evolution reaction (HER), CO 2 solubility limitations, catalyst corrosion and stability issues, and challenges in controlling product selectivity, all of which hinder industrial implementation. This review begins by analyzing the catalytic mechanisms underlying CO 2 RR pathways, laying the foundation for designing acidic CO 2 RR catalysts. An in‐depth analysis of the key factors limiting the use of acidic electrolytes is subsequently presented. We systematically summarize recent advances in achieving efficient CO 2 RR in acidic media, including interfacial microenvironment engineering, catalyst design, and electrolyzer strategy optimization. Finally, this review outlines future directions for acidic CO 2 electrolysis, including the development of corrosion‐resistant membrane electrode assemblies to advance this technology from the laboratory to industrial scale.