Renewable biomass-derived carbon-supported g-C3N4 doped with Ag for enhanced photocatalytic reduction of CO2

Constructing noble metal-doped g-C3N4/carbon composites is a feasible route to overcome the intrinsic drawbacks of pristine g-C3N4 for enhanced activity of CO2 photoreduction. Herein, a novel Ag-doped gC(3)N(4)/biomass-derived carbon composite with hollow bird's nest-like (Ag-g-C3N4/BN-C) is designed and prepared via a simple yet effective one-step pyrolysis method. In the Ag-g-C3N4/BN-C, the highlydispersed Ag nanoparticles (20-30 nm) with the surface plasmon resonance (SPR) effect act as a significant cocatalyst not only to efficiently trap the photogenerated electrons from g-C3N4 to boost the separation of photogenerated electron-hole pairs but also to produce additional active ``hot electrons, while the conductive quasi-spherical hollow structure of BN-C doubles the specific surface area with multiple reflections of light, providing abundant active sites and more utilization efficiency of light energy. As a result, the Ag-g-C3N4/BN-C exhibits a remarkably enhanced CO evolution rate of 33.3 lmol.g(-1.)h(-1Y) without addition of any sacrificial reagents and photosensitizers, superior to those of both the pristine g-C3N4 and many reported g-C3N4-based counterparts. The findings of this work demonstrate a good indication for integrating g-C3N4 with SPR-dependence noble metal and renewable biomass-derived carbon for enhanced CO2 photoreduction, which may be extended to modify other semiconductor materials for more photocatalytic applications with enhanced activity. (C) 2021 Elsevier Inc. All rights reserved.

Automated summary

Constructing noble metal-doped g-C3N4/carbon composites is an effective approach to enhance the activity of CO2 photoreduction. This study introduces a novel Ag-doped gC(3)N(4)/biomass-derived carbon composite with unique features, such as highly dispersed Ag nanoparticles and a conductive quasi-spherical hollow structure of BN-C, which significantly improve the CO evolution rate without the need for sacrificial reagents or photosensitizers.