Photocatalytic Dynamics of Organic Dye Degradation on Graphitic Carbon Nitride: An Integrated Experimental and Theoretical Investigation

Muhammad Amir Abbas; Jamaluddin Mahar; Nasir Ali; Muhammad Junaid; Muhammad Shahid Rasool

doi:10.5281/zenodo.19693515

المؤلفون

Muhammad Amir Abbas Institute of Chemistry, the Islamia University of Bahawalpur, Bahawalpur, Pakistan المؤلف
Jamaluddin Mahar Department of Chemistry, Quaid-E-Azam University Islamabad, Islamabad, Pakistan المؤلف
Nasir Ali Departments of Physics, Government Degree College Saleh Pat, Sukkur, Pakistan المؤلف
Muhammad Junaid Institute of Chemistry, the Islamia University of Bahawalpur, Bahawalpur, Pakistan المؤلف
Muhammad Shahid Rasool Departments of Chemistry, University of Karachi, Karachi, Pakistan المؤلف

DOI:

https://doi.org/10.5281/zenodo.19693515

الكلمات المفتاحية:

Graphitic carbon nitride; g-C₃N₄; Photocatalysis; Density functional theory; Frontier molecular orbitals; Quantum chemical descriptors; Molecular electrostatic potential; Visible-light degradation; Dye removal; Environmental remediation

الملخص

Graphitic carbon nitride (g-C₃N₄) is recognized as one of the most promising metal-free photocatalysts according to its chemical stability, optical activity in the visible region, and structural versatility. Nevertheless, the photocatalytic activity of g-C₃N₄ may usually be restricted by the low efficiency in charge separation and moderate redox potential. In the current study, the photocatalytic material of graphitic carbon nitride has been prepared by the straightforward thermal polycondensation of melamine and has been explored systematically. Through the X-ray diffraction technique, the material has been proved to have ordered layers with an interlayer distance of 0.324 nm, along with an average size of the crystallite of 90.9 nm. Moreover, it has unambiguously been shown that the material possesses considerable absorption in the visible region and has an optical bandgap of 2.61 eV according to the results of the UV-Visible spectra. The thermal properties of the photocatalytic material have been revealed by the thermal analysis, and it is confirmed that the material possesses good stability with few losses in masses at high temperatures along with the characteristic thermal transition at 350 °C. The density functional theory (DFT) calculations were performed with the aim of providing atomic-level validation and mechanistic insight into the electronic structure and reactivity of g-C₃N₄. Calculated frontier molecular orbitals and global quantum chemical descriptors are in good agreement with the experimentally observed semiconducting behavior and point to a favorable balance between electronic stability and charge-transfer capability. Molecular electrostatic potential analysis identifies nitrogen-rich regions as preferential reactive sites, thus supporting the material's photocatalytic and adsorption-driven degradation performance. The combination of experimental characterizations with computational chemistry provides a clear structure-property relationship that ensures g-C₃N₄ is a robust and efficient candidate for solar-driven photocatalysis and environmental remediation.

السير الشخصية للمؤلفين

Muhammad Amir Abbas، Institute of Chemistry, the Islamia University of Bahawalpur, Bahawalpur, Pakistan

Institute of Chemistry, the Islamia University of Bahawalpur, Bahawalpur, Pakistan
Jamaluddin Mahar، Department of Chemistry, Quaid-E-Azam University Islamabad, Islamabad, Pakistan

Department of Chemistry, Quaid-E-Azam University Islamabad, Islamabad, Pakistan
Nasir Ali، Departments of Physics, Government Degree College Saleh Pat, Sukkur, Pakistan

Departments of Physics, Government Degree College Saleh Pat, Sukkur, Pakistan
Muhammad Junaid، Institute of Chemistry, the Islamia University of Bahawalpur, Bahawalpur, Pakistan

Institute of Chemistry, the Islamia University of Bahawalpur, Bahawalpur, Pakistan
Muhammad Shahid Rasool، Departments of Chemistry, University of Karachi, Karachi, Pakistan

Departments of Chemistry, University of Karachi, Karachi, Pakistan

المراجع

1. Abbas, M. A. (2025). Advanced Synthesis and Multifunctional Characterization of Neodymium-Doped Ba₂NiCoFe₂₈₋ₓO₄₆ X-Type Hexagonal Ferrites: A Comprehensive Study of Structural, Morphological, and Electromagnetic Properties. Sch Acad J Biosci, 8, 1213-1227

2. Abbas, M. A., & Rasool, M. S. (2026). Eco-Friendly Synthesis of Ag–Co3O4 Nanoparticles for Visible-Light Photocatalysis and DFT-Based Nonlinear Optical Investigation. Chemical Technology and Engineering Applications, 1(1), 23-34.

3. Abbas, M. A., Junaid, M. J. M., Rasool, M. S., & Mahar, J. (2025). Structural and NLO Properties of Novel Organic 4-Bromo-4-Nitrostilbene Crystal: Experimental and DFT Study. International Research Journal of Management and Social Sciences, 6(4), 1-20.

4. Akhundi, A.; Zaker Moshfegh, A.; Habibi-Yangjeh, A.; Sillanpää, M. Simultaneous Dual-Functional Photocatalysis by g-C3N4-Based Nanostructures. ACS EST Eng. 2022, 2, 564–585.

5. Alizadeh, T.; Nayeri, S.; Hamidi, N. Graphitic carbon nitride (g-C3N4)/graphite nanocomposite as an extraordinarily sensitive sensor for sub-micromolar detection of oxalic acid in biological samples. RSC Adv. 2019, 9, 13096–13103.

6. Basivi, P.K.; Selvaraj, Y.; Perumal, S.; Bojarajan, A.K.; Lin, X.; Girirajan, M.; Kim, C.W.; Sangaraju, S. Graphitic carbon nitride (g–C3N4)–Based Z-scheme photocatalysts: Innovations for energy and environmental applications. Mater. Today Sustain. 2025, 29, 101069.

7. Beyer, J.; Mamakhel, A.; Søndergaard-Pedersen, F.; Yu, J.; Iversen, B.B. Continuous flow hydrothermal synthesis of phase pure rutile TiO2 nanoparticles with a rod-like morphology. Nanoscale 2020, 12, 2695–2702.

8. CRYSTAL—Basis Sets Library. Available online: https://www.crystal.unito.it/basis-sets.php (accessed on 24 March 2023).

9. Dandia, A.; Gupta, S.L.; Saini, P.; Sharma, R.; Meena, S.; Parewa, V. Structure couture and appraisal of catalytic activity of carbon nitride (g-C3N4) based materials towards sustainability. Curr. Res. Green Sustain. Chem. 2020, 3, 100039.

10. Dettori, R.; Goldman, N. Creation of an Fe3P Schreibersite Density Functional Tight Binding Model for Astrobiological Simulations. J. Phys. Chem. A 2025, 129, 583–595.

11. Erba, A.; Desmarais, J.K.; Casassa, S.; Civalleri, B.; Donà, L.; Bush, I.J.; Searle, V.; Maschio, L.; Daga, L.-E.; Cossard, A.; et al. CRYSTAL23: A Program for Computational Solid State Physics and Chemistry. J. Chem. Theory Comput. 2022.

12. Gatti, C.; Casassa, S. TOPOND 14 User’s Manual. Available online: https://www.crystal.unito.it/topond/topond.pdf (accessed on 24 March 2023).

13. Goldman, N.; Fried, L.E.; Lindsey, R.K.; Pham, C.H.; Dettori, R. Enhancing the accuracy of density functional tight binding models through ChIMES many-body interaction potentials. J. Chem. Phys. 2023, 158, 144112.

14. Green Chemistry|US EPA—epa.gov. Available online: https://www.epa.gov/greenchemistry (accessed on 13 May 2025).

15. Hartley, G.O.; Martsinovich, N. Computational design of graphitic carbon nitride photocatalysts for water splitting. Faraday Discuss. 2021, 227, 341–358.

16. Hayat, A.; Sohail, M.; Ali Shah Syed, J.; Al-Sehemi, A.G.; Mohammed, M.H.; Al-Ghamdi, A.A.; Taha, T.A.; Salem AlSalem, H.; Alenad, A.M.; Amin, M.A.; et al. Recent Advancement of the Current Aspects of g-C3N4 for its Photocatalytic Applications in Sustainable Energy System. Chem. Rec. 2022, 22, 202100310.

17. Im, C.; Kirchhoff, B.; Krivtsov, I.; Mitoraj, D.; Beranek, R.; Jacob, T. Structure and Optical Properties of Polymeric Carbon Nitrides from Atomistic Simulations. Chem. Mater. 2023, 35, 1547–1559.

18. Inoki, H.; Seo, G.; Kanai, K. Synthesis of graphitic carbon nitride under low ammonia partial pressure. Appl. Surf. Sci. 2020, 534, 147569.

19. Ismael, M. A review on graphitic carbon nitride (g-C3N4) based nanocomposites: Synthesis, categories, and their application in photocatalysis. J. Alloy. Compd. 2020, 846, 156446.

20. Jmol: An Open-Source Java Viewer for Chemical Structures in 3D. Available online: https://jmol.sourceforge.net (accessed on 24 March 2023).

21. Lee, J.H.; Jeong, S.Y.; Son, Y.D.; Lee, S.W. Facile fabrication of TiO2 quantum dots-anchored g-C3N4 nanosheets as 0D/2D heterojunction nanocomposite for accelerating solar-driven photocatalysis. Nanomaterials 2023, 13, 1565.

22. Li, Q.; Jiang, J.; Lin, B.; Ding, D.; Xu, H.; Wang, P.; Chen, Y. Understanding the Surface of g-C3N4, an Experimental Investigation of the Catalytic Active Site on the Interface. Catal. Lett. 2019, 149, 3296–3303.

23. Liu, N.; Li, T.; Zhao, Z.; Liu, J.; Luo, X.; Yuan, X.; Luo, K.; Luo, K.; He, J.; Yu, D.; et al. From Triazine to Heptazine: Origin of Graphitic Carbon Nitride as a Photocatalyst. ACS Omega 2020, 5, 12557–12567.

24. Liu, Y.; Huang, X.; Yu, Z.; Yao, L.; Guo, S.; Zhao, W. Environmentally Friendly Non-Metal Solar Photocatalyst C3N4 for Efficient Nitrogen Fixation as Foliar Fertilizer. ChemistrySelect 2020, 5, 7720–7727.

25. Papailias, I.; Todorova, N.; Giannakopoulou, T.; Plakantonaki, N.; Vagenas, M.; Dallas, P.; Anyfantis, G.C.; Arabatzis, I.; Trapalis, C. Enhancing the visible light photocatalytic activity of TiO2-based coatings by the addition of exfoliated g-C3N4. Catalysts 2024, 14, 333.

26. Pei, J.; Li, H.; Yu, D.; Zhang, D. g-C3N4-Based Heterojunction for Enhanced Photocatalytic Performance: A Review of Fabrications, Applications, and Perspectives. Catalysts 2024, 14, 825.

27. Porcu, S.; Castellino, M.; Roppolo, I.; Carbonaro, C.M.; Palmas, S.; Mais, L.; Casula, M.F.; Neretina, S.; Hughes, R.A.; Secci, F.; et al. Highly efficient visible light phenyl modified carbon nitride/TiO2 photocatalyst for environmental applications. Appl. Surf. Sci. 2020, 531, 147394.

28. Porcu, S.; Roppolo, I.; Salaun, M.; Sarais, G.; Barbarossa, S.; Casula, M.F.; Carbonaro, C.M.; Ricci, P.C. Come to light: Detailed analysis of thermally treated Phenyl modified Carbon Nitride Polymorphs for bright phosphors in lighting applications. Appl. Surf. Sci. 2020, 504, 144330.

29. Porcu, S.; Secci, F.; Ricci, P.C. Advances in Hybrid Composites for Photocatalytic Applications: A Review. Molecules 2022, 27, 6828.

30. Rhimi, B.; Wang, C.; Bahnemann, D.W. Latest progress in g-C3N4 based heterojunctions for hydrogen production via photocatalytic water splitting: A mini review. J. Phys. Energy 2020, 2, 042003.

31. Saeed, M., Akram, N., Naqvi, S. A. R., Usman, M., Abbas, M. A., Adeel, M., & Nisar, A. (2019). Green and eco-friendly synthesis of Co3O4 and Ag-Co3O4: Characterization and photo-catalytic activity. Green Processing and Synthesis, 8(1), 382-390.

32. Safaei, J.; Mohamed, N.A.; Mohamad Noh, M.F.; Soh, M.F.; Ludin, N.A.; Ibrahim, M.A.; Roslam Wan Isahak, W.N.; Mat Teridi, M.A. Graphitic carbon nitride (g-C3N4) electrodes for energy conversion and storage: A review on photoelectrochemical water splitting, solar cells and supercapacitors. J. Mater. Chem. A 2018, 6, 22346–22380.

33. Suyana, P.; Ganguly, P.; Nair, B.N.; Pillai, S.C.; Hareesh, U.S. Structural and compositional tuning in g-C3N4 based systems for photocatalytic antibiotic degradation. Chem. Eng. J. Adv. 2021, 8, 100148.

34. Villalobos, L.F.; Vahdat, M.T.; Dakhchoune, M.; Nadizadeh, Z.; Mensi, M.; Oveisi, E.; Campi, D.; Marzari, N.; Agrawal, K.V. Large-scale synthesis of crystalline g-C3N4 nanosheets and high-temperature H2 sieving from assembled films. Sci. Adv. 2022, 6, eaay9851.

35. Wang, Y.; Zhang, Y.; Li, B.; Luo, K.; Shi, K.; Zhang, L.; Li, Y.; Yu, T.; Hu, W.; Xie, C.; et al. Restacked melon as highly-efficient photocatalyst. Nano Energy 2020, 77, 105124.

36. Wategaonkar, S.; Pawar, R.; Parale, V.; Nade, D.; Sargar, B.; Mane, R. Synthesis of rutile TiO2 nanostructures by single step hydrothermal route and its characterization. Mater. Today Proc. 2020, 23, 444–451.

37. Zhou, T.T.; Zhao, F.H.; Cui, Y.Q.; Chen, L.X.; Yan, J.S.; Wang, X.X.; Long, Y.Z. Flexible TiO2/PVDF/g-C3N4 nanocomposite with excellent light photocatalytic performance. Polymers 2019, 12, 55.

38. Abbas, M. A., Mahar, J., Hameed, N., & Rasool, M. S. (2025). DFT-Guided Design of a Low-Band-Gap Pyrazoline Scaffold: The Critical Role of a Para-Nitro Substituent. Multidisciplinary Surgical Research Annals, 3(3), 461-503.

39. Abbas, M. A., Mahar, J., Khan, M. J., Rasool, M. S., & Khan, M. Z. (2025). IN SILICO INVESTIGATION OF 3, 6-DIPHENYL-[1, 2, 4] TRIAZOLO [3, 4-B][1, 3, 4] THIADIAZOLE DERIVATIVES AS EGFR MODULATORS FOR LUNG CANCER TREATMENT. The Cancer Research Review, 4(2), 243-308.

40. Abbas, M. A., Mahar, J., Rasool, M. S., Khan, M. J., & Khan, M. Z. (2025). The Dual Therapeutic Promise of Quinoa: Exploring Antidiabetic and Antioxidant Effects through Experimental and Computational Models. Multidisciplinary Surgical Research Annals, 3(3), 504-544.

41. Abbas, M. A., Junaid, M. J. M., Rasool, M. S., & Mahar, J. (2025). Structural and NLO Properties of Novel Organic 4-Bromo-4-Nitrostilbene Crystal: Experimental and DFT Study. International Research Journal of Management and Social Sciences, 6(4), 1-20.

42. Abbas, M. A., & Rasool, M. S. (2026). Eco-Friendly Synthesis of Ag–Co3O4 Nanoparticles for Visible-Light Photocatalysis and DFT-Based Nonlinear Optical Investigation. Chemical Technology and Engineering Applications, 1(1), 23-34.

43. Junaid, M., Rasool, M. S., Abbas, M. A., & Mahar, J. (2024). Formulation Development and Evaluation of a Bilayered Tablet Containing Dapagliflozin and Metformin. Global Research Journal of Natural Science and Technology, 2(3).

44. Akram, S., Abbas, M. A., Mahar, J., Rasool, M. S., & Junaid, M. INTERFACIAL DEFECT PASSIVATION AND PHOTOPHYSICAL ENGINEERING OF CSPBCL₃ QUANTUM DOTS VIA BISBENZIMIDAZOLIUM LIGANDS FOR ADVANCED ELECTRONIC DEVICES.

45. Abbas, M. A., Khan, M. Z., Atif, H. M., Shahzad, A., & Mahar, J. (2025). Computer-Aided Analysis of Oxino-bis-Pyrazolederivative as a Potential Breast Cancer Drug Based on DFT, Molecular Docking, and Pharmacokinetic Studies: Compared with the Standard Drug Tamoxifen. Indus Journal of Bioscience Research, 3(6), 535-537.