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Herein, an electrochemical (EC) system was applied as "co-catalyst" to enhance the activation of peroxymonosulfate (EC/Fe(III)/PMS) for efficient Sulfamethoxazole (SMX) degradation. The cathodic reduction reaction can facilitate electron transfer to Fe(III) and trigger the sustainable Fe(III)/Fe(II) redox cycle. Unexpectedly, in addition to hydroxyl radical (•OH) and sulfate radical (SO 4 •−), non-radicals mechanism including singlet oxygen (1O 2) and Fe(IV) were also found involved in EC/Fe(III)/PMS system. The degradation of SMX in EC/Fe(III)/PMS system was accomplished by the collaboration of radicals and non-radicals oxidation. The generation routes and mechanisms of involved reactive oxygen species (ROS) were explored. The relative contributions of •OH, SO 4 •−, and nonradical species for the degradation of SMX were calculated to 4.75 %, 25.31 %, and 69.94 %, respectively. Besides, multiple degradation pathways of SMX were proposed by identifying the formed byproducts. The EC/Fe(III)/PMS process could efficiently degrade SMX under the influence of co-existing ions and inactivate pathogens in the wastewater. [Display omitted] • Electrochemical system was used as a "co-catalyst" to promote the Fe(III)/Fe(II) redox cycle. • SMX is effectively degraded with a weak electrical current consumption in EC/Fe(III)/PMS system. • EC/Fe(III)/PMS system is mainly a non-radical pathway dominated by 1O 2 and Fe(IV). • EC/Fe(III)/PMS system demonstrated the ability to simultaneously eliminate contaminants and pathogens. [ABSTRACT FROM AUTHOR]

[Display omitted] • A heterogeneous catalytic system of NaBiO 3 for PMS without light irradiation was investigated. • Both radical (SO 4 −• and •OH) and non-radical (1O 2) were contributed to BPAF degradation. • The contribution rate of 1O 2 , · SO- 4, and · OH was calculated as 80.4%, 8.7%, and 9.9%, respectively. It has been shown previously that the NaBiO 3 (NBO) could efficiently photocatalytically degrade organic contaminants because of its excellent photocatalytic property. In this study, we proposed a heterogeneous catalytic system of NBO for peroxymonosulfate (PMS) without light irradiation. The results showed that NBO/PMS exhibited excellent performance toward bisphenol AF (BPAF) degradation and mineralization. The effectiveness of the NBO/PMS system was also investigated in different multicomponent systems. The effects of initial pH, NBO dosages, and PMS concentration for BPAF degradation were also investigated. Radical quenching experiments combined with electron spin resonance analysis indicated that singlet oxygen (1O 2) was the main reactive oxygen species, and · SO 4 - and · OH– radicals participated in the process. X-ray photoelectron spectroscopy revealed the main catalytic mechanism: lattice oxygen (O vac) was extruded during the transformation of Bi(V) to Bi(III) to form and activate oxygen (O*), and the generated O* between the [BiO 6 ] regular octahedral layers reacted with PMS on the NBO surface to form 1O 2. Based on the results of the Bi element, it is suggested that the activation process proceeded through electron transfer from NBO to PMS. The stability of NBO and applicability of the NBO/PMS system in a natural water environment were explored. This work provides a novel approach to PMS activation and the potential use of NBO for the decontamination of organic pollutants. [ABSTRACT FROM AUTHOR]