One-pot synthesis of mesosilica/nano covalent organic polymer composites and their synergistic effect in photocatalysis

• Published in: Chinese journal of catalysis 2021-10, Vol.42 (10), p.1821-1830
• Main Authors: Li, Chengbin, Li, He, Li, Chunzhi, Ren, Xiaomin, Yang, Qihua
• Format: Article
• Language: English
• Subjects: Covalent organic polymers; Hybrid materials; Mesoporous silica; Photocatalysis; Reductive dehylogenation reaction; Synergy effect
• ISSN: 1872-2067; 1872-2067
• DOI: 10.1016/S1872-2067(21)63812-3

Organic-inorganic hybrid materials provide a desirable platform for the development of novel functional materials. Here, we report the one-pot synthesis of mesoporous hybrid nanospheres by the in-situ sol-gel condensation of tetraethoxysilane around surfactant micelle-confined nano covalent organic polymer (nanoCOP) colloids. The hybrid nanospheres containing nanoCOPs uniformly distributed in the mesosilica network, inherited the visible light responsive properties of the nanoCOPs. The turnover frequency of the hybrid nanospheres is almost 12 times that of its corresponding bulk COP counterpart for the photocatalytic reductive dehalogenation of α-bromoacetophenone, which is attributed to activation of the Hantzsch ester reductant by the hydroxyl group. The existence of a volcano relationship between the activity and nanoCOP/mesosilica ratio confirmed the synergistic effect between nanoCOP and mesosilica. Our preliminary results suggest that hybridization of semiconductors and reactant-activating materials is an efficient strategy for enhancing the activity of a catalyst for photocatalysis. Hybridization of mesoporous silica-nanoCOPs on the nanoscale is reported for the first time, and the synergistic effect between the nanoCOPs and mesosilica in the photocatalytic reductive dehalogenation of α-bromoacetophenone is established.