Transformation of Porous Organic Cages and Covalent Organic Frameworks with Efficient Iodine Vapor Capture Performance.

The reaction of 5,5'-([2,2'-bipyridine]-5,5'-diyl)diisophthalaldehyde (BPDDP) with cyclohexanediamine and [benzidine (BZ)/[2,2'-bipyridine]-5,5'-diamine (BPDA)], respectively, affords a nitrogen-rich porous organic cage BPPOC and two two-dimensional (2D) covalent organic frameworks (COFs), USTB-1 and USTB-2 (USTB = University of Science and Technology Beijing), under suitable conditions. Interestingly, BPPOC with a single-crystal X-ray diffraction structure is able to successfully transform into USTB-1 and USTB-2 (newly converted COFs denoted as USTB-1c and USTB-2c, respectively) upon exchange of the imine unit of cyclohexanediamine in the cage by BZ and BPDA. Such a transformation also enables the isolation of analogous COFs (USTB-3c and USTB-4c) on the basis of an isostructural organic cage, BTPOC, which is derived from 5,5'-([2,2'-bithiophene]-4,4'-diyl)diisophthalaldehyde (BTDDP) and cyclohexanediamine.

Atomically Dispersed NiN Sites on Highly Defective Micro-Mesoporous Carbon for Superior CO Electroreduction.

Direct electrochemical conversion of CO to CO product powered by renewable electricity is widely advocated as an emerging strategy for alleviating CO emissions while addressing global energy issues. However, the development of low-cost and efficient electrocatalysts with high Faradaic efficiency for CO production (FE ) and high current density remains a grand challenge. Herein, a robust single nickel atomic site electrocatalyst, which features isolated and dense single atomic NiN sites anchored on highly defective hierarchically micro-mesoporous carbon (Ni-SAs/HMMNC-800), to enable enhanced charge transport and more exposed active sites for catalyzing electrochemical CO -to-CO conversion, is reported.

Porphyrin Coordination Polymer with Dual Photocatalytic Sites for Efficient Carbon Dioxide Reduction.

The resurgence of visible light photocatalysis for carbon dioxide reduction reaction (CORR) has resulted in the generation of various homogeneous and heterogeneous paradigms. Herein, a new system has been established by incorporating dual catalytic sites into porous coordination polymer toward the photocatalysis of CORR. A functional ligand, 5,10,15,20-tetrakis[4'-(terpyridinyl)phenyl]porphyrin (TTPP), has been used to assemble discrete divalent nickel ions into the coordination polymer (TTPP-Ni) through metal bis(terpyridine) nodes.