Photocatalytic CO2 conversion over single-atom MoN2 sites of covalent organic framework

The application of covalent organic framework (COF) for photocatalytic CO 2 conversion has received more and more attention. However, it is still a challenge for photocatalytic conversion of CO 2 with atmosphere concentration to high added value hydrocarbons products (C x H y ) such as CH 4 and C 2 H 4 . Here, integrating the advantages of micropore structure and single atom catalysis, we introduced single- atom MoN 2 sites into COF to construct Mo-COF materials. The aberration-COrrected high-angle annular dark-field scanning transmission electron microscopy (HAADF- STEM) confirms that Mo single atom on COF. Mo-COF can reduce CO 2 to C x H y under visible light with a selectivity of 42.92 % and C 2 H 4 product was found for the the first time. In-situ fourier transform infrared spectrometer (In situ FT-IR) and theoretical calculation showed that the introduction of single-atom MoN 2 sites is the key to improving the catalysis performance. It also provides a new idea for converting CO 2 into high added value C x H y products.