Thermal and Photocatalytic Conversion of CO₂ to Ethanol: Advances in Catalyst Design, Challenges, and Opportunities

The transition toward a carbon-neutral energy system requires efficient strategies to convert CO₂ into energy-dense liquid fuels capable of decarbonizing sectors where electrification remains impractical. Among emerging renewable synthetic fuels, ethanol is particularly attractive due to its high energy density, favorable handling properties, chemical versatility, and compatibility with existing infrastructure. Thermocatalytic and photocatalytic CO₂ conversion routes have advanced rapidly, yet challenges in activity, selectivity, and catalytic durability continue to limit large-scale deployment. This review surveys catalytic systems developed for CO₂-to-ethanol conversion, covering both thermocatalytic and light-driven approaches. Proposed reaction mechanisms are discussed with emphasis on how CC coupling pathways depend on alloying, promoter effects, support properties, tandem configurations, and semiconductor design. Catalyst performance is compared across studies, and systems are grouped according to metal abundance and prevalence, highlighting strategies that enhance ethanol selectivity and productivity. Overall, this review integrates experimental performance with mechanistic insights from spectroscopy and theory, provides a comprehensive overview of the state of the art, and identifies key challenges and future directions for achieving higher yields, improved selectivity, and long-term stability in renewable ethanol production from captured CO₂.