Fabrication of novel g-C3N4 nanocrystals decorated Ag3PO4 hybrids: Enhanced charge separation and excellent visible-light driven photocatalytic activity

Meng Sun; Qi Zeng; Xia Zhao; Yu Shao; Pengge Ji; Changqian Wang; Tao Yan; Bin Du

doi:10.1016/j.jhazmat.2017.06.003

Fabrication of novel g-C₃N₄ nanocrystals decorated Ag₃PO₄ hybrids: Enhanced charge separation and excellent visible-light driven photocatalytic activity

J Hazard Mater. 2017 Oct 5:339:9-21. doi: 10.1016/j.jhazmat.2017.06.003. Epub 2017 Jun 2.

Authors

Meng Sun¹, Qi Zeng², Xia Zhao², Yu Shao³, Pengge Ji², Changqian Wang³, Tao Yan², Bin Du⁴

Affiliations

¹ School of Resources and Environment, University of Jinan, Jinan, 250022, PR China; State Key Laboratory of Photocatalysis on Energy and Environment, Research Institute of Photocatalysis, Fuzhou University, Fuzhou, 350116, PR China.
² School of Resources and Environment, University of Jinan, Jinan, 250022, PR China.
³ State Key Laboratory of Photocatalysis on Energy and Environment, Research Institute of Photocatalysis, Fuzhou University, Fuzhou, 350116, PR China.
⁴ School of Resources and Environment, University of Jinan, Jinan, 250022, PR China. Electronic address: dubin61@gmail.com.

PMID: 28609728
DOI: 10.1016/j.jhazmat.2017.06.003

Abstract

Graphitic carbon nitride (g-C₃N₄) nanocrystals (NCs) decorated Ag₃PO₄ hybrids were synthesized by a facile method. The obtained samples were characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscope (SEM), transmission electron microscope (TEM), and UV-vis diffuse reflectance spectra (DRS). The SEM and TEM images showed that the as-prepared Ag₃PO₄ were composed of particles with diameters of 200-500nm, while the obtained nanocrystalline g-C₃N₄ were composed of smaller particles with average diameter of 10nm. For nanocrystalline g-C₃N₄/Ag₃PO₄ hybrids, the particle surfaces of Ag₃PO₄ were decorated with numerous g-C₃N₄ NCs, result in a larger contact area between g-C₃N₄ and Ag₃PO₄. The photocatalytic performances were evaluated by decomposing MO, phenol, bisphenol A, and RhB under visible light. Compared with Ag₃PO₄ and g-C₃N₄, the g-C₃N₄/Ag₃PO₄ hybrid (mass ratio=1:4) exhibited the best activity, which was much higher than that of bulk-g-C₃N₄/Ag₃PO₄ composite under the same conditions. The enhanced activities should be mainly ascribed to the enhanced separation efficiency of photo-generated carriers, which was proved by the photoluminescence (PL) spectra measurement. Controlled experiments proved that O₂^- and h⁺ played the chief role in the degradation process. A possible Z-scheme degradation mechanism of organic contaminant over g-C₃N₄/Ag₃PO₄ hybrid was proposed.

Keywords: Degradation; Organic pollutant; Photocatalyst; Visible light; g-C(3)N(4)/Ag(3)PO(4).