Donor-acceptor covalent organic framework/g-C3N4 hybrids for efficient visible light photocatalytic H2 production

Photocatalytic water splitting is a promising strategy for hydrogen energy production. However, it is still challenging to develop efficient and stable photocatalytic systems. Herein, a donor-acceptor type covalent organic framework (COF) was used to construct TBTA/g-C3N4 hybrids by the in situ condensation procedure of 2,4,6-triformylphloroglucinol (TP) and 4,4 '-(benzo-1,2,5-thiadiazole-4,7-diyl)dianiline (BTDA) on g-C3N4. The obtained hybrids displayed higher photocatalytic activity than the individual components. The H-2 evolution rate of the hybrids achieves 11.73 mmol g(-1) h(-1) without a noble metal, which is competitive with cutting-edge g-C3N4 hybrid materials, and can be further increased to 26.04 mmol g(-1) h(-1) with Pt as a co-catalyst. A series of experimental methods combined with theoretical calculations have demonstrated that TBTA/g-C3N4 hybrids exhibit broad visible light absorptions and appropriate energy levels, resulting in an efficient charge separation upon irradiation and in turn excellent photocatalytic activity.

Automated summary

This study demonstrates the successful enhancement of photocatalytic activity through the preparation of donor-acceptor type covalent organic framework (COF) hybrids. The obtained hybrids showed high H2 evolution rate without the need for noble metals, reaching 11.73 mmol g(-1) h(-1), which can be further increased to 26.04 mmol g(-1) h(-1) with Pt as a co-catalyst. Experimental methods combined with theoretical calculations confirmed the efficient charge separation and excellent photocatalytic activity of the TBTA/g-C3N4 hybrids.