Influence of Sulfur Doping of Crystalline Carbon Nitride on Photocatalytic Hydrogen Evolution from Alcohol–Aqueous Solutions Under Visible Light

• Published in: Theoretical and experimental chemistry Vol. 59; no. 6; pp. 397 - 405
• Main Authors: Ovcharov, M. L., Glukhova, P. I., Korzhak, G. V., Kutsenko, O. S., Stara, T. R., Kuchmiy, S. Ya
• Format: Journal Article
• Language: English
• Published: New York Springer US 2024; Springer Nature B.V
• Subjects: Aqueous solutions; Carbon; Carbon nitride; Catalytic activity; Chemistry; Chemistry and Materials Science; Chemistry/Food Science; Electromagnetic absorption; Ethanol; Heat treatment; Hydrogen evolution; Melamine; Palladium; Photocatalysis; Pyrolysis; Sulfur; sulfur; crystalline carbon nitride; photocatalysis; molecular hydrogen
• ISSN: 0040-5760; 1573-935X
• DOI: 10.1007/s11237-024-09798-5

The influence of sulfur on the morphology, spectral, and photocatalytic properties of bulk (S-g-C
3
N
4
) and crystalline carbon nitride (S-CGCN), obtained by the pyrolysis of melamine–S
8
mixtures and additional thermal treatment of S-g-C
3
N
4
in the eutectic melt of KCl and LiCl salts, has been investigated. It is shown that crystalline carbon nitride obtained in the presence of 5 wt.% of S
8
(5S-CGCN) demonstrate the highest photocatalytic activity in the hydrogen evolution process from water–ethanol solutions under the effect of visible light. The effective quantum yield of H
2
formation with the participation of 5S-CGCN and metal co-catalysts (palladium and gold) is Φ ≈ 100% at λ = 405 nm, which is almost twice as much as with the participation of unmodified CGCN. The high activity of 5S-CGCN can be associated with more intensive absorption of light, better separation of photogenerated charges, and suppression of their recombination.