2D/2D Z-scheme-based α-Fe2O3 @NGr heterojunction implanted with Pt single-atoms for remarkable photocatalytic hydrogen evolution

• Published in: Applied catalysis. B, Environmental Vol. 330; p. 122586
• Main Authors: Dao, Vandung, Cipriano, Luis A., Ki, Sang-Woo, Yadav, Sunny, Wang, Wenmeng, Di Liberto, Giovanni, Chen, Kai, Son, Hoki, Yang, Jin-Kyu, Pacchioni, Gianfranco, Lee, In-Hwan
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 05.08.2023
• Subjects: 2D/2D core-shell; Direct Z-scheme; Hematite; Nitrogen-doped graphene; Photocatalytic hydrogen evolution; Single-atoms; Hematite; Photocatalytic hydrogen evolution; 2D/2D core-shell; Nitrogen-doped graphene; Single-atoms; Direct Z-scheme
• ISSN: 0926-3373; 1873-3883
• DOI: 10.1016/j.apcatb.2023.122586

Direct Z-scheme designs perform well in light-to-fuel conversion. Here, an active and stable ternary Z-scheme core-shell heterojunction for photocatalytic hydrogen evolution (PHE) is fabricated consisting of hexagonal 2D α-Fe2O3 (as photocatalyst II) and 2D nitrogen-doped graphene (NGr as photocatalyst I) functionalized with the Pt single-atoms (SAs) cocatalyst. Under visible light, the 2D/2D α-Fe2O3 @NGr3PtSAs (NGr shell thickness of 3 nm and Pt loading of 0.5 wt%) achieves a remarkable PHE of 6.4 µmol mgcat−1 h–1, which is 16.4- and 3.28-times higher than those of free NGr (0.39 µmol mgcat−1 h–1) and binary α-Fe2O3 @NGr3 (1.95 µmol mgcat−1 h–1), thus outperforming the currently-advanced PHE catalysts. The outstanding performance is due to the superiority of a direct 2D/2D Z-scheme core-shell fabrication, including a large surface area for light harvesting, facile charge separation and transfer, and the workability of Pt SAs sites. Theoretical investigations provide additional insight into the mechanistic process of the ternary system for PHE reactions. [Display omitted] •A three-factored Z-scheme core-shell heterojunction is prepared for hydrogen evolution.•Under visible light, α-Fe2O3 @NGr3PtSAs reaches a high evolution rate of 6.4 µmol mgcat−1 h–1.•Our finding surpasses the currently-advanced hydrogen production photocatalysts.•Achievement is due to the excellence of a direct ternary 2D/2D Z-scheme core-shell fabrication.•Theoretical studies provide additional insight into the process of catalytic reactions.