Abstract The activation of CO 2 represents one of the most enduring challenges in catalysis, energy conversion, and carbon utilization. Recent studies reveal that excess electron density, whether localized on metallic clusters, delocalized within π‐conjugated organic frameworks, or transiently formed as radical anions, plays the decisive role in breaking the thermodynamic inertness of CO 2 . This review integrates experimental and theoretical advances, tracing the evolution of anionic activation of CO 2 from Pt hydride cluster anions to nitrogen‐doped polyaromatic catalysts. By connecting in vacuo spectroscopy, density functional theory (DFT), and ab initio molecular dynamics (AIMD), we delineate a unified electronic framework linking associative and dissociative activation, static and dynamic electron donation, and metal versus metal‐free paradigms. The role of the CO 2 radical anion in photocatalysis is discussed alongside the emerging design principles for next‐generation catalysts that exploit charge accumulation rather than expensive metallic centers.
Noh et al. (Fri,) studied this question.