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Journal of Nanomaterials
Volume 2019, Article ID 8175803, 8 pages
https://doi.org/10.1155/2019/8175803
Research Article

Preparation of Ag-Coated SiO2@TiO2 Core-Shell Nanocomposites and Their Photocatalytic Applications towards Phenol and Methylene Blue Degradation

1School of Environmental & Municipal Engineering, Lanzhou Jiaotong University, Lanzhou 730070, China
2Gansu Environmental Monitoring Center, Lanzhou 730020, China

Correspondence should be addressed to Xue-chang Ren; moc.liamtoh@8961gnahcxr

Received 2 July 2019; Accepted 24 August 2019; Published 15 October 2019

Guest Editor: Fei Ke

Copyright © 2019 Ning Fu et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

Ag-coated SiO2@TiO2 (Ag-SiO2@TiO2) core-shell nanocomposites were synthesized by a two-step method, which combined hydrothermal process and photodeposition. The morphology, structure, composition, and optical properties of the Ag-coated SiO2@TiO2 nanocomposites were extensively characterized by field-emission scanning microscopy (FE-SEM), transmission electron microscopy (TEM), energy-dispersive X-ray spectroscopy (EDS), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and Fourier-transform infrared spectra (FT-IR spectra). The anatase TiO2 nanoparticles (5-10 nm) with high surface area were loaded on SiO2 spheres (200-300 nm) in the form of SiO2@TiO2 core-shell nanoparticle with a porous shell of controlled thickness (10–30 nm). Ag nanoparticles of different mass concentrations were photodeposited on SiO2@TiO2 core-shell structure with particle sizes of about 10-20 nm. The results showed that Ag nanoparticles increased the photocatalytic activity of SiO2@TiO2 core-shell nanoparticle improved the degradation of phenol and methylene blue under UV irradiation. The experimental results showed that Ag nanoparticles with mass concentrations of 6% had the highest photocatalytic activity on SiO2@TiO2 core-shell nanoparticles.