Highly Dispersed Zr-Promoted CO ₂ Adsorption for Methanol Synthesis on Pd/In ₂ O ₃ Nanorods

This study presents the development of a highly dispersed PdZr/In2O3 catalyst composed of atomic Zr, Pd clusters, and In2O3 nanorods. This catalyst enhanced the adsorption of CO2 at oxygen vacancies for methanol synthesis, thereby promoting the conversion of CO2 and improving methanol selectivity. As confirmed by experiments, atomic Zr facilitated CO2 adsorption at oxygen vacancies on In2O3 and enhanced H2 transport over Pd clusters, promoting CO2 hydrogenation while suppressing over-reduction to improve reaction durability. Furthermore, Zr4+ incorporated into In2O3 crystal lattices strengthened the electron metal–support interaction (EMSI) between Pd and In2O3, enabling Pd to donate more electrons and thereby enhance hydrogen delivery capacity. Additionally, Zr doping generated abundant surface oxygen vacancies on the In2O3 nanorods, improving CO2 adsorption. Therefore, Zr doping increased the CO2 conversion to 16.5% and the methanol selectivity to 65.1%, resulting in a space-time yield of 0.70 gMeOH·gcat–1·h–1.