Incorporation of Engineered Cu ⁰ /Cu ⁺ Interfaces in Metal‐Organic Frameworks for Boosting CO ₂ Hydrogenation to Methanol

Abstract

ABSTRACT The Cu‐based materials are an important category of catalysts for CO 2 hydrogenation to methanol, in which Cu 0 and Cu + species have been widely acknowledged to play key roles in the reaction. Herein, a series of metal‐organic frameworks (MOFs), namely UiO‐66(n) with exposed ─COOH groups, are fabricated by employing both terephthalic acid and 1,2,4‐benzenetricarboxylic acid linkers. Following by introducing Cu nanoparticles, Cu@UiO‐66(n) are synthesized. By regulating the amount of exposed ─COOH groups on the MOF pore wall, the interaction between Cu and the MOF support is regulated. This ─COOH microenvironment regulates the overall Cu 0 /Cu + ratio in the supported Cu species, thereby tuning the Cu 0 /Cu + interfacial descriptor, which is closely associated with the CO 2 hydrogenation performance. The Cu@UiO‐66(25) featuring the longest Cu 0 /Cu + interface achieves a methanol space‐time yield of 694 g kg cat −1 h −1 and methanol selectivity of 92.8% at 250 °C and 4 MPa, far surpassing other counterparts. This work provides a deep understanding of the synergistic effect between Cu 0 and Cu + species in catalytic CO 2 hydrogenation.