Deciphering structural performance indicators of ZnZrOx catalysts forthe hydrogenation of CO2 to methanol - OING

The hydrogenation of CO2 to methanol is a promising technology to utilize CO2 and close the carbon cycle due to methanol’s versatile applications as a fuel additive, or platform chemical for fine/bulk chemical production. Among the materials that have been proposed to catalyze this reaction, ZnZrOx mixed metal oxides have shown great potential owing to their remarkable selectivity (> 80 %) and high stability. Initially, it was proposed that highly dispersed Zn within a tetragonal ZnZrOx solid solution yield the most active catalyst. However, it has been suggested recently that partially reduced, amorphous surface ZnO supported on ZrO2 displays a comparable activity for methanol synthesis as the initially reported, co-precipitated, ZnZrOx catalysts. Furthermore, some reports have argued that co-precipitated ZnZrOx is in fact not a homogeneous solid solution, but rather a mixed oxide comprised of ZnO nanoclusters within the ZrO2 lattice. Hence, the active site for CO2 hydrogenation