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Your search keyword '"Zhang, Shuai‐Bing"' showing total 195 results
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195 results on '"Zhang, Shuai‐Bing"'

25. Relative Local Electron Density Tuning in Metal‐Covalent Organic Frameworks for Boosting CO2 Photoreduction.

Author

Zhang, Mi, Huang, Pei, Liao, Jia‐Peng, Yang, Ming‐Yi, Zhang, Shuai‐Bing, Liu, Yu‐Fei, Lu, Meng, Li, Shun‐Li, Cai, Yue‐Peng, and Lan, Ya‐Qian

Subjects
ELECTRON density, CARRIER density, METAL clusters, SPECIFIC gravity, PHOTOCATALYSTS, PHOTOREDUCTION
Abstract

The high local electron density and efficient charge carrier separation are two important factors to affect photocatalytic activity, especially for the CO2 photoreduction reaction. However, the systematic studies on the structure‐functional relationship regarding the above two factors based on precisely structure model are rarely reported. Herein, as a proof‐of‐concept, we developed a new strategy on the evaluation of local electron density by controlling the relative electron‐deficient (ED) and electron‐rich (ER) intensity of monomer at a molecular level based on three rational‐designed vinylene‐linked sp2 carbon‐covalent organic frameworks (COFs). As expected, the as‐prepared vinylene‐linked sp2 carbon‐conjugated metal‐covalent organic framework (MCOFs) (VL‐MCOF‐1) with molecular junction exhibited excellent activities for CO2‐to‐HCOOH conversion (283.41 μmol g−1 h−1) and high selectivity of 97.1 %, much higher than the VL‐MCOF‐2 and g‐C34N6‐COF, which is due to the synergistic effect of the multi‐electronic metal clusters (Cu3(PyCA)3) (PyCA=pyrazolate‐4‐carboxaldehyde) as strong ER roles and cyanopyridine units as ED roles and active sites, as well as the boosted photo‐induced charge separation efficiency of vinyl connection and increased light utilization ability. These results not only provide a strategy for regulating the electron‐density distribution of photocatalysts at the molecular level but also offers profound insights for metal clusters‐based COFs to effective CO2 conversion. [ABSTRACT FROM AUTHOR]

Published
2023
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45. 3D Covalent Organic Frameworks with 16-Connectivity for Photocatalytic C(sp3)–C(sp2) Cross-Coupling

Author

Lu, Meng, Zhang, Shuai-Bing, Li, Run-Han, Dong, Long-Zhang, Yang, Ming-Yi, Huang, Pei, Liu, Yu-Fei, Li, Ze-Hui, Zhang, Han, Zhang, Mi, Li, Shun-Li, and Lan, Ya-Qian

Abstract

The connectivity (valency) of building blocks for constructing 3D covalent organic frameworks (COFs) has long been limited to 4, 6, 8, and 12. Developing a higher connectivity remains a great challenge in the field of COF structural design. Herein, this work reports a hierarchical expansion strategy for making 16-connected building blocks to construct 3D COFs with sqc topology. The [16 + 2] construction achieved by condensation between a 16-connected carbazolyl dicyanobenzene-based building block (CzTPN) and linear diamino linkers (BD or Bpy) affords two 3D COFs (named CzBD COF and CzBpy COF). Furthermore, attributed to the well-organized donor–acceptor (D–A) heterojunction, the Ni chelated CzBpy COF (Ni@CzBpy COF) exhibits excellent performance for photoredox/Ni dual catalytic C(sp3)–C(sp2) cross-coupling of alkyltrifluoroborates with aryl halides, achieving a maximum 98% conversion and 94% yield for various substrates. This work developed the first case of high-connectivity COFs bearing 16-connected units, which is the highest connectivity reported until now, and achieved efficient photocatalysis applications, thus greatly enriching the possibilities of COFs.

Published
2024
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