In Situ Pyrolysis of ZIF-67 to Construct Co<sub>2</sub>N<sub>0.67</sub>@ZIF-67 for Photocatalytic CO<sub>2</sub> Cycloaddition Reaction
Lingjing Jiang, Dengqi Wu, Zishan Huang, Fengfeng Chen, Kai Chen, Aziz B. Ibragimov, Junkuo Gao
Abstract
The development of heterogeneous catalysts with abundant active sites is pivotal for enhancing the efficiency of photothermal CO 2 conversion. Herein, we report the construction of Co 2 N 0.67 @ZIF-67 through the in situ pyrolysis of ZIF-67 under low-temperature pyrolysis conditions. During the pyrolysis process, the crystal structure of ZIF-67 is predominantly preserved concurrently with the formation of Co 2 N 0.67 nanoparticles (NPs) within the ZIF-67 pores. The optimal catalyst Co 2 N 0.67 @ZIF-67(450,2) not only possesses high photothermal efficiency but also can efficiently activate CO 2 . Benefiting from these characteristics, Co 2 N 0.67 @ZIF-67(450,2) exhibited significant catalytic activity in the photocatalytic cycloaddition of CO 2 and epichlorohydrin. The yield of (chloromethyl)ethylene carbonate reached 95%, which is more than 4 times higher than that of ZIF-67 under visible light irradiation (300 W·m 2 Xe lamp, 3 h). This study could offer an alternative approach to enhance the photocatalytic activity of MOFs through low-temperature pyrolysis.