Rational Design and Modulation of In₂O₃-Based Catalysts for Efficient CO₂ Hydrogenation to Methanol

To achieve the global carbon neutrality target by approximately 2050, the development and deployment of carbon-negative technologies based on green chemical principles have become an urgent strategic priority. Among various CO₂ valorization routes, catalytic CO₂ hydrogenation to methanol (CH₃OH, CHM) has attracted intensive interest, in which indium oxide (In₂O₃) stands out as a highly promising candidate due to its unique properties in stabilizing key reaction intermediates for CH₃OH synthesis. However, the practical implementation of pristine In₂O₃ is severely hindered by insufficient catalytic activity. To address the bottlenecks, a variety of multidimensional modification strategies have been rationally designed and extensively explored to tune the characteristics of In₂O₃-based catalysts, which include modulating properties of In₂O₃, tailoring properties of metal promoters and regulating metal-In₂O₃ interactions. In this review, we commence with a systematic discussion of the reaction mechanisms governing CHM over In₂O₃-based catalysts, then provide an in-depth summary and critical evaluation of the modification strategies for the rational design of In₂O₃-based catalysts, and finally highlight the most challenging issues and possible solutions in this rapidly evolving field to guide the rational design of the next-generation of efficient In₂O₃-based catalytic systems for sustainable CHM and the advancement of the circular carbon economy.