Dual functional Ag2MoO4/thickness-controlled g-C3N4 composites for enhanced photocatalytic and adsorption activity

• Published in: Journal of the Taiwan Institute of Chemical Engineers 2025-02, Vol.167, p.105863, Article 105863
• Main Authors: Zhou, Xuanbo, Guo, Xu, Dong, Lihong, Zhou, Wanli, Li, Xiumei
• Format: Article
• Language: English
• Subjects: Adsorption performance; Ag2MoO4; g-C3N4; Photocatalytic activity; Pollutants
• ISSN: 1876-1070
• DOI: 10.1016/j.jtice.2024.105863

•g-C3N4 with different thicknesses is prepared by thermal oxidation etching method.•Loading Ag2MoO4 on g-C3N4 with different thicknesses exhibits different performance.•Ag2MoO4/g-C3N4 show great bifunctional properties of photocatalysis and adsorption. Nanocomposites have a wide range of applications in the field of energy and environment, especially in the treatment of organic pollutants and radioactive materials in water, so the development of new nanocomposites for the treatment of environmental pollution is urgent. The morphology of g-C3N4 has a significant impact on its properties. The g-C3N4 with different thicknesses were prepared by thermal oxidation exfoliation and etching of bulk g-C3N4 (CNB) under air atmosphere, and separately combined with Ag2MoO4. The samples were characterized with X-ray diffraction, scanning electron microscopy (SEM), UV–vis diffuse reflectance spectra, X-ray photoelectron spectroscopy. The results showed that the composite of Ag2MoO4 formed of g-C3N4 with a thickness of 24.7 nm exhibited excellent photocatalytic degradation property. The photo-degradation rate of methylene blue (MB), rhodamine B (RhB) and methyl orange (MO) were 97.9 % (30 min), 94.2 % (40 min) and 91.3 % (40 min), respectively. Differently, when Ag2MoO4 is combined with g-C3N4 with a thickness of 10.0 nm, which show excellent adsorption performance. The adsorption amount of I2 can reach 4.487 g/g under 75 °C of saturated I2 vapor. And the nanocomposite manifested splendid adsorption efficiency of MB (95.8 %, 6 min), RhB (93.2 %, 6 min) and MO (94.3 %, 6 min), respectively. The nanocomposite achieved the bifunctional characteristics of degradation of organic pollutants and efficient adsorption. G-C3N4 nanosheets with different thicknesses were synthesized by self-modification of polymeric melon units through thermally treating (CNB) under an air atmosphere (a weak oxidizing atmosphere). During the heating process, CNB can be thermally oxidized into a thickness of 24.7 nm (CN-2), 16.4 nm (CN-4) and 10.0 nm (CN-6) nanosheets by overcoming the weak van der Waals forces present between the layers. The Ag2MoO4/thickness-controlled g-C3N4 composites were fabricated by a convenient chemical deposition method at room temperature. Surprisingly, the nanocomposites formed by the deposition of Ag2MoO4 on g-C3N4 nanosheets with different thicknesses exhibit excellent performance in photocatalytic degradation and adsorption, respectively. [Display omitted]