Recently, Prof. Yan Yu’s group at College of Materials Science and Engineering of Fuzhou University published a research article entitled “Integrating Single Ni Sites into Biomimetic Networks of Covalent Organic Frameworks for Selective Photoreduction of CO2” inChemical Science.
Selective photoreduction of CO2 into a given product is a great challenge but desirable. Inspired by natural photosynthesis occurring in the hierarchical networks over non-precious molecular metal catalysts, we demonstrate an integration of single Ni sites into the hexagonal pores of polyimide covalent organic frameworks (PI-COFs) for selective photoreduction of CO2 to CO. The single Ni sites in the hexagonal pores of the COFs serve as active sites for CO2 activation and conversion, while the PI-COFs not only act as photosensitizer to generate charge carries but also exert a promoting effect on the selectivity. The optimized PI-COF with triazine ring exhibits an excellent activity and selectivity. A possible intra- and inter-molecular charge transfer mechanism was proposed, in which the photogenerated electrons in PI-COFs are efficiently separated from the central ring to the diimide linkage, and then transferred to the single Ni active sites, as evidenced by theoretical calculations.
Link: https://pubs.rsc.org/en/content/articlepdf/2020/sc/d0sc01747g
