Nanoscale Confinement of Indium Oxide for Enhanced CO2 Hydrogenation to Methanol

Research on CO₂ hydrogenation catalysts, particularly In₂O₃-based materials, is crucial for developing sustainable CO₂ utilization and chemical production technologies, contributing to a cleaner future. We address the critical challenge of efficient and stable CO₂ conversion by developing a novel Zr-doping strategy to enhance In₂O₃ catalyst performance for CO₂ hydrogenation to methanol. Our key contribution is identifying the nanoscale confinement effect as crucial for optimizing both the activity and stability of In₂O₃ catalysts. By leveraging this nanoscale confinement effect, we have precisely controlled the size, dispersion, and reducibility of In₂O₃ nanoparticles, resulting in the formation and stabilization of highly active In₂O_3–x with oxygen vacancies. This confinement also effectively suppresses In⁰ migration and sintering, dramatically improving catalyst stability. The resulting Zr-doped catalysts exhibit significantly higher activity and stability compared to the undoped In₂O₃/ZrO₂ catalyst, achieving a remarkable space-time yield of 4.708 g_MeOH g_In^–1 h^–1 and demonstrating durability under industrially relevant conditions. This discovery offers a promising new direction for the rational design of high-performance CO₂ hydrogenation catalysts and lays the foundation for future advances in sustainable catalysis.