Synergetic effect of photocatalysis and peroxymonosulfate activated by ZnM2O4/SBA–15 (M = Fe and Mn) for enhanced degradation efficiency of doxycycline hydrochloride under visible light irradiation

• Published in: Materials today communications Vol. 31; p. 103315
• Main Authors: Li, Di, Zhao, Qianqian, Li, Hongmiao, Long, Mingyang
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01.06.2022
• Subjects: Peroxymonosulfate; Photocatalysis; Synergetic effect; Visible–light; ZnM2O4/SBA–15; Synergetic effect; Visible–light; Peroxymonosulfate; Photocatalysis; ZnM2O4/SBA–15
• ISSN: 2352-4928; 2352-4928
• DOI: 10.1016/j.mtcomm.2022.103315

ZnM2O4 (M = Fe and Mn) nanoparticles were prepared via sol–gel process, and they showed lower photocatalytic activity for the degradation of doxycycline hydrochloride under visible light irradiation. After the ZnM2O4 nanoparticles were loaded in the channel of SBA–15, the removal rate of doxycycline hydrochloride was increased by more than ten times. It could be attributed to that the ZnM2O4/SBA–15 photocatalyst possessed larger surface area, thereby improving the photocatalytic activity. For further enhance the degradation efficiency of doxycycline hydrochloride, ZnM2O4/SBA–15 were used to activate peroxymonosulfate under visible–light irradiation. Besides photo–generated e–/h+, Fe, Zn and Mn in ZnM2O4/SBA–15 also could activate peroxymonosulfate to produce SO4•– radicals, so the combined activation effects of photo-generated e–/h+ and transition metals on PMS to produce SO4•– radicals could enhance the degradation efficiency obviously. The main influencing factors (peroxymonosulfate dosage, pH value, temperature, inorganic anions and so on) on degradation efficiency of doxycycline hydrochloride were studied in detail. It was found that the degradation efficiency of ZnFe2O4/SBA–15 was higher than ZnMn2O4/SBA–15, and it could be ascribed to the difference in the surface area. The radical scavenger experiments and EPR spectroscopy proved sulfate radical was the main active substance. In addition, the mechanisms of ZnM2O4/SBA–15 activating peroxymonosulfate under visible–light irradiation were proposed. [Display omitted] •ZnM2O4/SBA−15 photocatalysts were synthesized by sol-gel method.•Peroxymonosulfate was activated by photogenerated e−/h+, Fe, Zn and Mn.•The SO4•− radicals mainly contributed to doxycycline hydrochloride degradation.