Photocatalytic degradation of 2,4,6-tribromophenol over Fe-doped ZnIn₂S₄: Stable activity and enhanced debromination

详细信息    查看全文

• 作者：Bo Gao ; ^{gbljd1986@163.com} ; Lifen Liu ; ^{yuzhe25521@yahoo.com.cn} ; Jiadong Liu ; Fenglin Yang
• 关键词：2 ; 4 ; 6-TBP ; 2 ; 4 ; 6-tribromophenol ; DBP ; dibromophenol ; BP ; bromophenol ; MB ; methylene blue ; ZVI NPs ; zerovalent iron nanoparticles ; NZVI ; nanoscale zerovalent iron
• 刊名：Applied Catalysis B: Environmental
• 出版年：2013
• 出版时间：17 January, 2013
• 年：2013
• 卷：129
• 期：Complete
• 页码：89-97
• 全文大小：1249 K

文摘

Fe doped ZnIn₂S₄ catalyst was prepared and tested for photocatalytic degradation of 2,4,6-tribromophenol (2,4,6-TBP), it was more efficient in debromination and total organic carbon (TOC) removal, compared with TiO₂ (P25) and ZnIn₂S₄. The preparation of Fe-ZnIn₂S₄ involved a facile hydrothermal ZnIn₂S₄ synthesis process at low temperature and without templates, followed by chemical reductive deposition of Fe. The catalysts were characterized using scanning electron microscopy (SEM) equipped with an X-ray energy dispersive spectroscopy (EDS), TEM and HRTEM, FT-IR spectra, X-ray diffraction (XRD) and UV-vis diffuse reflectance spectra. The band gaps of ZnIn₂S₄ and Fe-ZnIn₂S₄ calculated from the onset of the absorption edges were 2.12 eV and 2.05 eV, respectively. The calculated pseudo-first-order constants (K_r) were in the order of TiO₂ (0.022 min^?1) < 0.5 wt % Fe-TiO₂ (0.0369 min^?1) < ZnIn₂S₄ (0.362 min^?1) < 0.5 wt % Fe-ZnIn₂S₄ (0.436 min^?1). After 1 h reaction by Fe-ZnIn₂S₄, the released bromide concentration was 17.6mg l^?1, which was 1.11 and 2.69 times higher than ZnIn₂S₄ and TiO₂ (P25), respectively. The increase in TOC removal was 7 % and 33 % compared to ZnIn₂S₄ and TiO₂ (P25), respectively. The repeated tests proved that the synthesized Fe-ZnIn₂S₄ was stable, reusable and durable in degradation of 2,4,6-TBP. The possible cycle of iron species and a tentative debromination pathway were proposed.