Synthesis and structural morphological characteristics of graphitic carbon nitride modified with polar hydroxyl groups

Keywords

synthesis, graphitic carbon nitride, surface modification, hydroxyl groups, ultrasonic treatment, hydrogen peroxide, photocatalyst.

Cite as

Sukhatskiy Y. V., Shepida М. V., and Korniy S. A. Synthesis and structural morphological characteristics of graphitic carbon nitride modified with polar hydroxyl groups. Physicochemical Mechanics of Materials. 2026. 62(4), 51-56. https://doi.org/10.15407/pcmm2026.04.051

Abstract

The surface of g-C₃N₄ was modified with polar hydroxyl groups through g-C₃N₄ treating with an aqueous solution of hydrogen peroxide in an ultrasonic (US) field. The diffraction patterns showed a shift of the diffraction peaks corresponding to the (002) plane for modified g-C₃N₄ samples towards larger values of 2q angles (from 27.3 to 27.4°) compared to un­modified g-C₃N₄, which indicated a decrease in the interlayer distance of the photocatalysts (from 0.3266 to 0.3254 nm) and, accordingly, an increased rate of charge carrier transfer. Scanning electron microscopy and energy-dispersive X-ray analysis confirmed an increase in the content of hydroxyl groups on the g-C₃N₄ surface with increasing the duration of US treatment. The chemical structure of modified g-C₃N₄ was evaluated by Fourier transform infrared spectroscopy. A significant decrease in the absorption intensity in the range of 3000–3400 cm^–1 was found with US treatment duration of 60 min, which can be explained by possible exfoliation of g-C₃N₄ layers and fracture of interlayer hydrogen bonds, oxidation of hydroxyl groups on the g-C₃N₄ surface to carboxyl groups, or “screening” of hydroxyl groups due to steric hindrance.

References

1. Y.H. Gao, W.L. Zhao, and Y. Chen, “g-C3N4 modified by hydroxyl group on the surface prepared by double salt enhanced the visible light photocatalytic activity,” Diam. Relat. Mater., 116 (2021). Art. no. 108425. https://doi.org/10.1016/j.diamond.2021.108425
2. N.S.N. Hasnan, M.A. Mohamed, and Z.A. Mohd Hir, “Surface physicochemistry modification and structural nanoarchitectures of g-C3N4 for wastewater remediation and solar fuel generation,” Adv. Mater. Technol., 7, Is. 5 (2022). Art. no. 2100993. https://doi.org/10.1002/admt.202100993
3. S. Hu, K. Wang, P. Li, F. Wang, X. Kang, and G. Wu, “The effect of hydroxyl group grafting on the photocatalytic phenolic compounds oxidation ability of g-C3N4 prepared by a novel H2O2-alkali hydrothermal method,” Appl. Surf. Sci., 513 (2020). Art. no. 145783. https://doi.org/10.1016/j.apsusc.2020.145783
4. X. Liang, J. Fan, D. Liang, Y. Xu, Y. Zhi, H. Hu, and X. Qiu, “Surface hydroxyl groups functionalized graphite carbon nitride for high efficient removal of diquat dibromide from water,” J. Colloid Interface Sci., 582, 70-80 (2021). https://doi.org/10.1016/j.jcis.2020.08.011
5. Y. Sukhatskiy, M. Sozanskyi, Z. Znak, “Pure and doped graphitic carbon nitride for peroxymonosulfate activation in advanced oxidation processes of dyes in aqueous media: A review,” J. Environ. Chem. Eng., 14, Is. 5 (2026). Art. no. 123706. https://doi.org/10.1016/j.jece.2026.123706
6. B. Sindhav, A.N. Kadam, M.G. Mali, M. Misra, and H.A. Parbat, “Current advances in g-C3N4 modification for enhanced antimicrobial and photocatalytic applications,” Discov. Appl. Sci., 8 (2026). Art. no. 605. https://doi.org/10.1007/s42452-026-08575-4
7. Z. Li, X. Meng, and Z. Zhang, “Fabrication of surface hydroxyl modified g-C3N4 with enhanced photocatalytic oxidation activity,” Catal. Sci. Technol., 9, Is. 15, 3979-3993 (2019). https://doi.org/10.1039/C9CY00550A
8. Z. Ma, L. Zhang, L. Zang, and F. Yu, “Modification of g-C3N4 by the surface alkalinization method and its photocatalytic depolymerization of lignin,” Mater., 18, 14 (2025). Art. no. 3350. https://doi.org/10.3390/ma18143350
9. Y.V. Sukhatskiy, M.V. Shepida, and M.Y. Holovchuk, “Synthesis of nanosized MgMn2O4 spinel by co-precipitation in the ultrasonic field,” Mater. Sci., 60, Is. 2, 205-211 (2024). https://doi.org/10.1007/s11003-025-00873-3
10. J. Chen, M. Yang, H. Zhang, Y. Chen, Y. Ji, R. and Yu, Z. Liu, “Boosting the activation of molecular oxygen and the degradation of Rhodamine B in polar-functional-group-modified g-C3N4,” Molecules, 29, 16 (2024). Art. no. 3836. https://doi.org/10.3390/molecules29163836
11. Z. Mao, J. Chen, Y. Yang, L. Bie, B.D. Fahlman, and D. Wang, “Modification of surface properties and enhancement of photocatalytic performance for g-C3N4 via plasma treatment,” Carbon, 123, 651-659 (2017). https://doi.org/10.1016/j.carbon.2017.08.020
12. H. Che, X. Gao, J. Chen, J. Hou, Y. Ao, and P. Wang, “Iodide-induced fragmentation of polymerized hydrophilic carbon nitride for high-performance quasi-homogeneous photocatalytic H2O2 production,” Angew. Chem. Int. Ed., 60, Is. 48, 25546-25550 (2021). https://doi.org/10.1002/anie.202111769
13. X. Bu, J. Li, S. Yang, J. Sun, Y. Deng, Y. Yang, G. Wang, Z. Peng, P. He, X. Wang, G. Ding, J. Yang, and X. Xie, “Surface modification of C3N4 through oxygen-plasma treatment: A simple way toward excellent hydrophilicity,” ACS Appl. Mater. Interfaces, 8, Is. 45, 31419-31425 (2016). https://doi.org/10.1021/acsami.6b10516
14. X. Xu, Z. Huang, L. Tan, Z. Zhang, B. Chen, X. Xia, G. Cheng, X. Chen, “Surface modification of g-C3N4 for enhanced photocatalytic activity via a simple illumination in pure water,” Appl. Surf. Sci., 672 (2024). Art. no. 160794. https://doi.org/10.1016/j.apsusc.2024.160794
15. N. An, Y. Zhao, Z. Mao, D.K. Agrawal, and D. Wang, “Microwave modification of surface hydroxyl density for g-C3N4 with enhanced photocatalytic activity,” Mater. Res. Express, 5, Is. 3 (2018). Art. no. 035502. https://doi.org/10.1088/2053-1591/aab0fa