Metal-free four-in-one modification of g-C3N4 for superior photocatalytic CO2 reduction and H2 evolution

Mahmoud Kamal Hussien, Amr Sabbah, Mohammad Qorbani, Mohamed Hammad Elsayed, Putikam Raghunath, Tsai Yu Lin, Shaham Quadir, Hong Yi Wang, Heng Liang Wu, Der Lii M. Tzou, Ming Chang Lin, Po Wen Chung, Ho Hsiu Chou, Li Chyong Chen*, Kuei Hsien Chen

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

28 Scopus citations

Abstract

Utilization of g-C3N4 as a single photocatalyst material without combination with other semiconductor remains challenging. Herein, we report a facile green method for synthesizing a metal free modified g-C3N4 photocatalyst. The modification process combines four different strategies in a one-pot thermal reaction: non-metal doping, porosity generation, functionalization with amino groups, and thermal oxidation etching. The as-prepared amino-functionalized ultrathin nanoporous boron-doped g-C3N4 exhibited a high specific surface area of 143.2 m2 g−1 which resulted in abundant adsorption sites for CO2 and water molecules. The surface amino groups act as Lewis basic sites to adsorb acidic CO2 molecules, which can also serve as active sites to facilitate hydrogen generation. Besides, the simultaneous use of ammonium chloride as a dynamic gas bubble template along with thermal oxidation etching efficiently boosts the delamination of the g-C3N4 layers to produce ultrathin sheets; this leads to stronger light–matter interactions and efficient charge generation. Consequently, the newly modified g-C3N4 achieved selective gas-phase CO2 reduction into CO with a production yield of 21.95 µmol g−1, in the absence of any cocatalyst. Moreover, a high hydrogen generation rate of 3800 µmol g-1h−1 and prominent apparent quantum yield of 10.6% were recorded. This work opens up a new avenue to explore different rational modifications of g-C3N4 nanosheets for the efficient production of clean energy.

Original languageEnglish
Article number132853
JournalChemical Engineering Journal
Volume430
DOIs
StatePublished - 15 Feb 2022

Keywords

  • Gas bubble template
  • Hydrogen generation
  • Metal-free photocatalyst
  • g-CN, CO reduction

Fingerprint

Dive into the research topics of 'Metal-free four-in-one modification of g-C3N4 for superior photocatalytic CO2 reduction and H2 evolution'. Together they form a unique fingerprint.

Cite this