In2O3-ZrO2 catalysts for CO2 hydrogenation to methanol: from binary nanostructure and oxygen vacancies to ternary systems and dynamic reconstruction.

CO2 hydrogenation to methanol (CHM) represents a promising route for carbon recycling and sustainable chemical production. Among the various catalyst systems investigated, In2O3-ZrO2-based catalysts have emerged as one of the most effective platforms owing to their high methanol selectivity, excellent CO2 activation, and tunable interfacial structures. This review summarizes recent advances in the development of In2O3-ZrO2 catalysts for CHM, with particular emphasis on the structure-activity relationships governing catalytic performance. First, progress in binary In2O3-ZrO2 catalysts is discussed, focusing on nanostructural engineering and Ov regulation strategies for enhancing CO2 adsorption, activation and methanol selectivity. Subsequently, transition-metal modified In2O3-ZrO2 systems are reviewed, highlighting how promoter metals regulate reactant activation, hydrogen spillover, electronic structure, crystal-phase synergy, and reaction-induced catalyst reconstruction. The dynamic evolution of catalyst structures under reaction conditions and its impact on catalytic performance are critically examined. Furthermore, recent mechanistic insights derived from in situ and/or operando characterization and theoretical calculations are summarized, leading to a unified understanding of the dynamic interfacial mechanism governing methanol synthesis over In2O3-ZrO2 catalysts. Finally, the remaining challenges associated with catalyst stability, scalable synthesis and industrial implementation are discussed, together with future opportunities in atomic-scale interface engineering, multi-component catalyst design and in situ and/or operando-guided catalyst development.