Facet-inheritance strategy to enrich Cu(1 0 0) in Cu/ZnO catalyst for high-efficiency CO2 hydrogenation to methanol

Increasing the content of the Cu(1 0 0) facet in Cu/ZnO-based catalyst is an effective strategy for boosting their catalytic performance in CO 2 hydrogenation to methanol. However, the Cu(1 1 1) facet rather than the Cu(1 0 0) facet has the lowest surface energy for both CuO and metallic Cu, making it challenging to enrich Cu(1 0 0) facet through traditional preparation methods. Herein, leveraging the intrinsically lowest surface energy of the (1 0 0) facet in Cu 2 O, we proposed a scalable solid-phase synthesis method starting with Cu 2 O/ZnO composites, proceeding via CuO/ZnO composites as an intermediate, and then reduced to prepare Cu/ZnO catalysts with high Cu(1 0 0) facet content. Due to the facet inheritance behavior of Cu during redox processes under mild conditions, the Cu(1 0 0) facet content in the synthesized Cu/ZnO catalyst was 1.7-fold higher than that of the catalyst prepared by the traditional preparation method. The increased Cu(1 0 0) facet facilitates CO 2 bridge adsorption as well as hydrogen activation and spillover, thus enhancing catalytic performance. Under 260 °C and 3 MPa, the methanol selectivity and space–time yield of the optimized Cu/ZnO catalyst reached 64 % and 920 mg·g cat −1 ·h −1 , respectively. The facet engineering strategy significantly improves catalytic performance of Cu/ZnO catalysts and holds great potential for industrial-scale applications.