Carbon-Based Catalysts for Electrocatalytic CO ₂ Reduction Reaction via Heteroatom Doping and Metal Doping: Influencing Factors, Mechanisms, and Economic Analysis

The electrocatalytic carbon dioxide reduction reaction (ECO2RR) has emerged as a key strategy for mitigating the greenhouse effect and addressing energy shortages due to their mild reaction conditions and high controllability. Carbon-based catalysts, characterized by their low cost, high specific surface area, high conductivity, and excellent chemical stability, are emerging as alternatives to precious-metal systems. Their catalytic performance ─ activity, stability, and selectivity ─ can be modulated through coordination, size, and synergistic effects, driving the strategic design of doped carbon materials (e.g., via heteroatom or metal doping) to optimize active sites, tailor electronic structures, and steer reaction pathways. However, the practical implementation depends not only on catalytic performance but equally on overarching systemic factors of sustainability and economic viability. Life Cycle Assessment (LCA) and Technology-Economic Analysis (TEA) underscore that the environmental footprint and commercial feasibility of ECO2RR systems are fundamentally governed by the integration of renewable electricity and optimized process design, respectively. Also, this paper systematically reviews the reaction pathways and product distributions of carbon-based catalysts in ECO2RR. Subsequently, it analyzes the influence of key factors such as potential, pH, electrolyte type, reactor design, and CO2 source on reaction performance, aiming to improve the interaction between reactants and reaction efficiency. Additionally, the applications of single-atom and multiatom doped carbon-based catalysts for the ECO2RR were discussed, with an emphasis on their underlying reaction mechanisms. Finally, this article concludes by highlighting the major challenges and prospects associated with carbon-based catalysts in ECO2RR, providing valuable insights for future research and development.