g-C3N4 nanoparticle@porous g-C3N4 composite photocatalytic materials with significantly enhanced photo-generated carrier separation efficiency

• Published in: Journal of materials research Vol. 35; no. 16; pp. 2148 - 2157
• Main Authors: Shen, Qianhong, Wu, Chengyan, You, Zengyu, Huang, Feilong, Sheng, Jiansong, Zhang, Fang, Cheng, Di, Yang, Hui
• Format: Journal Article
• Language: English
• Published: New York, USA Cambridge University Press 28.08.2020; Springer International Publishing; Springer Nature B.V
• Subjects: Applied and Technical Physics; Biomaterials; Carbon; Carbon nitride; Carrier lifetime; Composite materials; Conduction bands; Crystal structure; Efficiency; Energy bands; Energy Conversion and Storage Materials; Energy gap; Inorganic Chemistry; Light irradiation; Materials Engineering; Materials research; Materials Science; Morphology; Nanoparticles; Nanotechnology; Optical properties; Photocatalysis; Porous materials; Porous media; Self-assembly; Separation; Spectrum analysis; Valence band; X ray photoelectron spectroscopy; Zeta potential; interface; nanostructure; photochemical
• ISSN: 0884-2914; 2044-5326
• DOI: 10.1557/jmr.2020.182

A novel g-C3N4 nanoparticle@porous g-C3N4 (CNNP@PCN) composite has been successfully fabricated by loading g-C3N4 nanoparticles on the porous g-C3N4 matrix via a simply electrostatic self-assembly method. The composition, morphological structure, optical property, and photocatalytic performance of the composite were evaluated by various measurements, including XRD, SEM, TEM, Zeta potential, DRS, PL, FTIR, and XPS. The results prove that the nanolization of g-C3N4 leads to an apparent blueshift of the absorption edge, and the energy band gap is increased from 2.84 eV of porous g-C3N4 to 3.40 eV of g-C3N4 nanoparticle (Fig. 6). Moreover, the valence band position of the g-C3N4 nanoparticle is about 0.7 eV lower than that of porous g-C3N4. Therefore, the photo-generated holes and electrons in porous g-C3N4 can transfer to the conduction band of g-C3N4 nanoparticle, thereby obtaining higher separation efficiency of photo-generated carriers as well as longer carrier lifetime. Under visible-light irradiation, 6CNNP@PCN exhibits the highest photocatalytic performance (Fig. 8) on MB, which is approximately 3.4 times as that of bulk g-C3N4.