Environmental application of chlorine-doped graphitic carbon nitride: Continuous solar-driven photocatalytic production of hydrogen peroxide

• Published in: Journal of hazardous materials Vol. 436; no. C; p. 129251
• Main Authors: Li, Mengqiao, Zheng, Qinmin, Durkin, David P., Chen, Hanning, Shuai, Danmeng
• Format: Journal Article
• Language: English
• Published: United States Elsevier B.V 15.08.2022; Elsevier
• Subjects: Doping; Engineering; Environmental Sciences & Ecology; Graphitic carbon nitride; INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY; Metal-free photocatalysts; Sustainable production of H2O2; Sustainable production of H2O2; Metal-free photocatalysts; Doping; Graphitic carbon nitride
• ISSN: 0304-3894; 1873-3336
• DOI: 10.1016/j.jhazmat.2022.129251

Solar-driven photocatalytic generation of H2O2 over metal-free catalysts is a sustainable approach for value-added chemical production. Here, we synthesized chlorine-doped graphitic carbon nitride (Cl-doped g-C3N4) through a solvothermal method to effectively produce H2O2 with a rate of 1.19 ± 0.06 µM min−1 under visible light irradiation, which was improved by 104 times compared to pristine g-C3N4. Continuous net production of H2O2 was realized at a rate of 2.78 ± 0.10 µM min−1 up to 54 h with isopropanol as the hole scavenger, whereas H2O2 production was only sustained for ~ 6 h without scavengers. Both molecular simulations and advanced spectroscopic characterizations elucidated that the Cl dopant increased the charge transfer rate, decreased the bandgap, and reduced the activation energy of the rate-limiting step of O2 reduction, all of which favored H2O2 production. This work implemented a novel metal-free photocatalyst for sustainable H2O2 production and elucidated the mechanism for promoting H2O2 production that can guide future photoreactive nanomaterial design. [Display omitted] •Cl-doped g-C3N4 was synthesized via a solvothermal method.•Cl dopant decreased the g-C3N4 bandgap and promoted charge transfer.•Cl dopant lowered the activation energy of the rate-determining step in H2O2 formation.•In the presence of isopropanol H2O2 was continuously produced on Cl-doped g-C3N4.