Large-scale synthesis of low-cost 2D metal–organic frameworks for highly selective photocatalytic CO₂ reduction

Two-dimensional metal–organic frameworks (2D MOFs), as a new type of 2D materials, have been widely applied in various applications because of their unique structures and exposed active sites. Herein, we reported two low-cost 2D MOFs constructed by a raw chemical succinic acid (SA), M-SA (M = Ni or Co), which served as efficient photocatalysts for the reduction of CO₂ to CO. Taking advantage of the thinness and open metal sites, the ultrathin Ni-SA nanosheets (ca. 3.6 nm) exhibited excellent CO production of 6.96(7) mmol·g⁻¹·h⁻¹ and CO selectivity of 96.6%. Photoelectrochemical tests and theoretical calculations further confirmed the higher charge transfer efficiency and unsaturated metal sites for promoting photocatalytic performances. More importantly, Ni-SA can also be synthesized in large-scale by an energy-saving method under room temperature, strongly suggesting its promising future and potential for practical applications.