International Journal of Nanoscience and Nanotechnology

International Journal of Nanoscience and Nanotechnology

Fabrication and Characterization of Doped and Coupled Graphitic Carbon Nitride-Based Nanostructures with Enhanced Optical and Electronic Properties

Document Type : Research Paper

Authors
1 Department of Nanotechnology, Graduate University of Advanced Technology, Kerman, Iran
2 Department of Mining Engineering, High Education Complex of Zarand, Shahid Bahonar University of Kerman, Kerman, Iran
10.22034/ijnn.2025.2055216.2640
Abstract
In this study, graphitic carbon nitride (g-C₃N₄) nanosheets were successfully synthesized and systematically modified through nitrogen and sulfur doping, as well as heterojunction coupling with bismuth vanadate (BiVO₄) and manganese-doped BiVO₄ (Mn-BiVO₄), to enhance their physicochemical and optoelectronic properties. A series of nanocomposites—including g-C₃N₄/BiVO₄, S-g-C₃N₄/BiVO₄, N-g-C₃N₄/BiVO₄, S-g-C₃N₄/Mn-BiVO₄, and N-g-C₃N₄/Mn-BiVO₄—were fabricated via controlled hydrothermal and coupling strategies. Comprehensive structural and morphological characterizations were performed using field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), energy-dispersive X-ray spectroscopy (EDX), and X-ray diffraction (XRD). The effects of doping and heterojunction formation on the optical band gap and light absorption capability were assessed using UV-Vis diffuse reflectance spectroscopy (DRS). The results confirmed that both elemental doping and heterostructure formation induced favorable modifications in the crystal structure and band alignment, thereby enhancing visible-light absorption and reducing the energy band gap. These findings demonstrate the potential of the designed nanostructures as efficient photocatalytic platforms for sustainable energy and environmental applications.
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