Highly Active Ir/In₂O₃ Catalysts for Selective Hydrogenation of CO₂ to Methanol: Experimental and Theoretical Studies

2021/03/17 by Chenyang Shen, Kaihang Sun, Zhitao Zhang +4
Chemical Engineering · Energy · Materials Science · #CO2 Reduction Techniques and Catalysts #Catalysts for Methane Reforming #Catalytic Processes in Materials Science

paper · doi:10.1021/acscatal.0c05628

openalex publication_date 2021/03/17 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/30

Abstract

Iridium (Ir) catalysts have been extensively applied in homogeneous and photocatalytic CO 2 conversion. However, CO 2 hydrogenation to methanol over the supported Ir catalyst in a heterogeneous flowing reactor has not been reported yet. Here, we report that indium oxide supported Ir catalyst (Ir/In 2 O 3 ) of high dispersion is very active for CO 2 hydrogenation to methanol. Compared to In 2 O 3, Ir/In 2 O 3 shows a significantly higher activity with even higher methanol selectivity. For example, CO 2 conversion of 17.7% is achieved on Ir/In 2 O 3 of 10 wt % Ir loading with methanol selectivity over 70% and high methanol space time yield of 0.765 g MeOH h –1 g cat –1 at 4/1 of the CO 2 /H 2 feed ratio, 21 000 h –1, 300 °C, and 5 MPa. With the catalysts tested, the higher Ir loading causes the higher activity. The catalyst characterization confirms an intense interaction between iridium and In 2 O 3, which causes the high dispersion of the Ir catalyst with the Ir–In 2 O 3 interface as the active site for selective hydrogenation of CO 2 into methanol. The Ir loading not only enhances the formation of oxygen vacancies but also stabilizes the vacancies for improved CO 2 activation. Further density functional theory studies reveal that the reverse water–gas shift route is more favorable over the formate route for CO 2 hydrogenation to methanol over Ir/In 2 O 3 catalyst.

Citations

• Efficient iterative schemes for<i>ab initio</i>total-energy calculations using a plane-wave basis set
• Challenges in the Greener Production of Formates/Formic Acid, Methanol, and DME by Heterogeneously Catalyzed CO₂Hydrogenation Processes
• Recent Advances in Carbon Dioxide Hydrogenation to Methanol via Heterogeneous Catalysis
• Selective hydrogenation of CO2 to methanol over Ni/In2O3 catalyst
• Rationally designed indium oxide catalysts for CO ₂ hydrogenation to methanol with high activity and selectivity
• Atomically dispersed Ptn+ species as highly active sites in Pt/In2O3 catalysts for methanol synthesis from CO2 hydrogenation
• Highly Selective Hydrogenation of CO₂ to Ethanol via Designed Bifunctional Ir₁–In₂O₃ Single-Atom Catalyst

Related

• CO₂ Hydrogenation to Methanol over In₂O₃-Based Catalysts: From Mechanism to Catalyst Development
• Highly Selective Hydrogenation of CO₂ to Ethanol via Designed Bifunctional Ir₁–In₂O₃ Single-Atom Catalyst
• Rationally designed indium oxide catalysts for CO ₂ hydrogenation to methanol with high activity and selectivity
• Spatially resolved reaction profiles of CO2 hydrogenation to methanol using in-based catalysts in a compact profile reactor
• Performance and stability of corundum‐type In2O3 catalyst for carbon dioxide hydrogenation to methanol