High-yield synthesis and optical properties of g-C3N4

• Main Authors: Yuan, Yanwen, Zhang, Lulu, Xing, Jun, Utama, M. Iqbal Bakti, Lu, Xin, Du, Kezhao, Li, Yongmei, Hu, Xiao, Wang, Shijie, Genç, Aziz, Dunin-Borkowski, Rafal, Arbiol, Jordi, Xiong, Qihua
• Other Authors: School of Electrical and Electronic Engineering
• Format: Article
• Language: English
• Published: 2016
• Subjects: Electron microscopy; Photocatalytic performance
• Online Access: https://hdl.handle.net/10356/82867; http://hdl.handle.net/10220/40351
• Institution: Nanyang Technological University

Graphitic carbon nitride (g-C3N4), a metal-free semiconductor with a band gap of 2.7 eV, has received considerable attention owing to its fascinating photocatalytic performances under visible-light. g-C3N4 exhibits high thermal and chemical stability and non-toxicity such that it has been considered as the most promising photocatalyst for environmental improvement and energy conservation. Hence, it is of great importance to obtain high-quality g-C3N4 and gain a clear understanding of its optical properties. Herein, we report a high-yield synthesis of g-C3N4 products via heating of high vacuum-sealed melamine powder in an ampoule at temperatures between 450 and 650 °C. Using transmission electron microscopy (TEM), scanning transmission electron microscopy (STEM), electron energy loss spectroscopy (EELS), thermogravimetric analysis (TGA), X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS), the chemical composition and crystallization of the as-produced g-C3N4 are demonstrated. A systematic optical study of g-C3N4 is carried out with several approaches. The optical phonon behavior of g-C3N4 is revealed by infrared and Raman spectroscopy, and the emission properties of g-C3N4 are investigated using photoluminescence (PL) spectroscopy, while the photocatalytic properties are explored by the photodegradation experiment.