A novel biomineralization regulation strategy to fabricate schwertmannite/graphene oxide composite for effective light-assisted oxidative degradation of sulfathiazole

Iron-based heterogeneous catalysts exhibit great peroxymonosulfate (PMS) activation ability to degrade persistent antibiotic pollutants, but the catalytic efficiency of this process is significantly affected by Fe(III)/Fe(II) conversion rate. Herein, we designed a novel biomineralization regulation process to fabricate graphene oxide modified schwertmannite composites (Sch-GO x ) as light-assisted PMS activator for enhancing sulfathiazole (STZ) degradation. More specifically, the introduction of GO in biomineralization process not only facilitated the dispersion of Sch, but also accelerated the regeneration of available surface-bound Fe(II) in resultant Sch-GO x through intramolecular electron transfer, thus promoting the activation of PMS. Compared with biosynthesized Sch without modification, the prepared Sch-GO 100 sample exhibited superior catalytic activity in light-assisted PMS activation process, 99.90 % removal efficiency of 78 μM STZ has been achieved within 30 min without pH adjustment (initial pH = 7.20). Abundant reactive oxygen species including SO 4 − , OH, O 2 − and 1 O 2 were responsible for the effective elimination of STZ. The potential degradation intermediates of STZ were investigated by liquid chromatography-mass spectrometry (LC-MS) and demonstrated to be less toxic than STZ using the ecological structure activity relationship program (ECOSAR). This study provided a facile and environmental-benign strategy of biomineralization regulation to fabricate effective iron-based PMS activator for environmental remediation.