Cr2 O3 Promoted In2 O3 Catalysts for CO2 Hydrogenation to Methanol.

Cr2 O3 was applied to study the modification of In2 O3 based catalysts for CO2 hydrogenation to methanol reaction. Combined with X-ray diffraction (XRD), scanning transmission electron microscopy (STEM), X-ray photoelectron spectroscopy (XPS), etc., the structure of the catalysts was characterized. The reaction performances for CO2 hydrogenation to methanol were evaluated on a stainless-steel fix-bed reactor. The results showed that solid solutions were formed for the Cr2 O3 promoted In2 O3 catalysts. The important role of electronic interaction between Cr2 O3 and In2 O3 was revealed in the hydrogenation reaction. In1.25 Cr0.75 O3 sample exhibited the highest methanol yield, which was 2.8 times higher than that of pure In2 O3 . No deactivation was observed for In1.25 Cr0.75 O3 sample during the 50 hours of reaction. The improved catalytic performance may be due to the formation of the solid solutions and the highest amount of oxygen vacancies.