Work

Synergistic effects of heterointerface and surface O vacancies in S-scheme BiO2-x/QL-COF heterojunction for efficient charge transfer: mechanism exploration and DFT calculations

Year: 2025

Type: article

Abstract: Covalent organic framework (COF) has great potential in the application of photocatalysis, but it still has the defect of easy recombination of photogenerated carriers. Herein, QL-COF was synthesized by carboxylation modification of LZU1 (Synthesis of the COF linked by 4-carboxyquinoline via the Doebner reaction (QL-COF).), and combined with BiO 2-x with oxygen vacancy to construct a novel S-scheme heterojunction BiO 2-x /QL-COF(BQ) by solvothermal method. Furthermore, its charge transfer mechanism has been demonstrated through Density Functional Theory (DFT) calculations. The photocatalytic performance of heterojunction BiO 2-x /QL-COF was evaluated by pollutant degradation, hydrogen production and CO 2 reduction. It was found the degradation rate of RhB over BQ-3 could reach almost 90 %. Moreover, the photocatalytic H 2 evolution rate of BQ-3 was up to 438.7 μmol g −1 h −1 , which is 7.6 times and 21 times that of QL-COF and BiO 2-x , respectively. And the evolution rate of photoreduction CO 2 to CO was 686.3 μmol g −1 h −1 . The enhancement of its photocatalytic performance may be mainly attributed to: (i) The construction of heterojunction improves the absorption capacity of heterojunction BQ to visible light; (ii) Oxygen vacancies form defect centers to trap photogenerated charges, which inhibit photogenerated carriers recombination, and provide more active sites for CO 2 adsorption; (iii) The electron-withdrawing effect of the carboxyl groups, which can effectively promote the migration of photogenerated carriers.

Source: Journal of Photochemistry and Photobiology A Chemistry

DOI: 10.1016/j.jphotochem.2025.116715

Authors: Xi Wang, Zhaosheng Zhu, Qingrong Cheng, Zhiquan Pan

Institution: Wuhan Institute of Technology

Language: English

Topic: Advanced Photocatalysis Techniques

Subfield: Renewable Energy, Sustainability and the Environment

Field: Energy

Domain: Physical Sciences

SDG: Affordable and clean energy

Open Access status: hybrid

Estimated APC paid: $3,470