An in depth mechanism insight of the degradation of multiple refractory pollutants via a novel SrTiO3/BiOI heterojunction photocatalysts

• Published in: Journal of catalysis Vol. 356; pp. 283 - 299
• Main Authors: Wen, Xiao-Ju, Niu, Cheng-Gang, Zhang, Lei, Liang, Chao, Zeng, Guang-Ming
• Format: Journal Article
• Language: English
• Published: Elsevier Inc 01.12.2017
• Subjects: BiOI; Heterojunction; Refractory pollutants; SrTiO3; SrTiO3; BiOI; Refractory pollutants; Heterojunction
• ISSN: 0021-9517; 1090-2694
• DOI: 10.1016/j.jcat.2017.10.022

SrTiO3/BiOI heterostructure photocatalysts were successfully fabricated through a facile chemical bath method with assistant of the ethylene glycol, which exhibit an efficient charge separation and excellent catalytic ability in removing different refractory pollutants. [Display omitted] •Novel SrTiO3/BiOI heterojunction photocatalysts were fabricated.•A wider application in the degradation of refractory pollutants.•The factors affecting the photocatalytic performance were investigated.•The degradation process of MO and OTTCH was monitor by 3D EEMs.•The in-depth mechanisms insight of charge separation. Novel SrTiO3/BiOI heterostructure photocatalysts were successfully fabricated through a facile chemical bath method with assistant of the ethylene glycol. The photocatalysts were applied to minimize methyl orange (MO), bisphenol A (BPA), antibiotic oxytetracycline hydrochloride (OTTCH) under visible light irradiation. The SrTiO3/BiOI composites exhibited excellent photocatalytic performance towards the different refractory pollutants. Especially, the sample of STB-22.12 possessed the best photocatalytic performance in all the obtained catalysts. Several reaction parameters affecting degradation such as initial concentration, ion species were investigated systematically. Three-dimensional excitation–emission matrix fluorescence spectroscopy (3D EEMs) was used to further investigate the MO and OTTCH molecule degradation process. The photocatalytic mechanism over composite photocatalyst is systematically investigated by active species trapping experiments, ESR technique and Mott–Schottky measurements. Moreover, the energy band alignments of SrTiO3/BiOI heterostructure were confirmed via combining DRS and XPS analysis, which provided strong support for the proposed mechanism. This work could provide a deeper insight for the heterojunction catalyst.