Although single-atom Cu sites exhibit high efficiency in CO 2 hydrogenation to methanol, they are prone to forming Cu nanoparticles due to reduction and aggregation under reaction conditions, especially at high temperatures. Herein, single-atom Cu sites stabilized by adjacent Na + ions have been successfully constructed within a metal-organic framework (MOF)-based catalyst, namely MOF-808-NaCu. It is found that the electrostatic interaction between the Na + and H δ- species plays a pivotal role in upholding the atomic dispersion of Cu in MOF-808-NaCu during CO 2 hydrogenation, even at temperatures of up to 275°C. This exceptional stabilization effect endows the catalyst with excellent activity (306 g·kg cat -1 ·h -1 ), high selectivity to methanol (93%) and long-term stability at elevated reaction temperatures, far surpassing the counterpart in the absence of Na + (denoted as MOF-808-Cu). This work develops an effective strategy for the fabrication of stable single-atom sites for advanced catalysis by creating an alkali-decorated microenvironment in close proximity.
(© The Author(s) 2024. Published by Oxford University Press on behalf of China Science Publishing & Media Ltd.)