Structure–reactivity relationships in CO2 hydrogenation to C2+ chemicals on Fe-based catalysts

Catalytic conversion of carbon dioxide (CO₂) to value-added products represents an important avenue towards achieving carbon neutrality. In this respect, iron (Fe)-based catalysts were recognized as the most promising for the production of C₂₊ chemicals via the CO₂ hydrogenation reaction. However, the complex structural evolution of the Fe catalysts, especially during the reaction, presents significant challenges for establishing the structure–reactivity relationships. In this review, we provide critical analysis of recent in situ and operando studies on the transformation of Fe-based catalysts in the hydrogenation of CO₂ to hydrocarbons and alcohols. In particular, the effects of composition, promoters, support, and particle size on reactivity; the role of the catalyst's activation procedure; and the catalyst's evolution under reaction conditions will be addressed.