期刊
APPLIED CATALYSIS B-ENVIRONMENTAL
卷 200, 期 -, 页码 484-492出版社
ELSEVIER
DOI: 10.1016/j.apcatb.2016.07.043
关键词
Photo-Fenton; Fe3O4@void@TiO2; Yolk-shell; TC degradation
资金
- National Nature Science Foundation of China [U140710223, 21237003, 21377038]
- National Basic Research Program of China (973 Program) [2013CB632403]
- Science and Technology Commission of Shanghai Municipality [14ZR1410700, 14230710500, 16JC1401400]
- Petro-China Innovation Foundation [2015D-5006-0402]
- Fundamental Research Funds for the Central Universities
Herein, we demonstrate the yolk-shell structured Fe3O4@void@TiO2 sphere as an efficient heterogeneous catalyst for the photo-Fenton-like degradation of tetracycline (TC). The composite was synthesized by first successively coating amorphous SiO2 and TiO2 shells around a Fe3O4 core via the sol-gel strategy to form Fe3O4@SiO2@TiO2, then crystallizing TiO2 and removing SiO2 through calcination and the ultrasonic ammonia-etching treatment, respectively. The particles are monodisperse and uniform in size (ca. 180 nm), where the diameter of the core is ca. 100 nm and the thickness of the shell is ca. 10 nm. This composite possesses anatase TiO2 shell with high crystallinity, superparamagnetic core with a saturation magnetization value of 28.71 emu/g and high specific surface area of 101 m(2) g(-1). It shows extremely high activity towards the degradation of TC (40 mg/L) in a wide pH range as demonstrated by almost 100% elimination efficiency at pH = 3 and ca. 75% at pH = 9 within 6 min. Moreover, benefitting from the superparamagnetism of the core, this composite could be magnetically recovered and reapplied in the TC degradation without significant loss of activity after 5 recycling (ca. 10%). The degradation curve can be well fitted by pseudo-first order model, where a kinetic constant of 0.51 min(-1) is achieved, much higher than those of Fe3O4@TiO2 (0.24min(-1)), hollow TiO2 (0.17 min(-1)), Fe3O4@SiO2@TiO2 (0.14 min(-1)) and Fe3O4 (0.11 min(-1)). The high activity is attributed to the efficient enrichment and confinement of reactants (TC and hydroxyl radicals) in the nanocavity of the yolk-shell structure, and the efficient reduction of Fe3+ to Fe2+ by the photo-generated electrons from the TiO2 shell. (C) 2016 Elsevier B.V. All rights reserved.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据