Co-Fe synergy in CoxFe1-xWO4: The new type peroxymonosulfate activator for sulfamethoxazole degradation

[Display omitted] •A new type PMS activator CoxFe1-xWO4 was developed for the SMX degradation.•Co-Fe synergism in the Co0.70Fe0.30WO4/PMS system was fully investigated.•Detailed reaction parameters in Co0.70Fe0.30WO4/PMS system were investigated.•The leaching level of cobalt ions (0.83 ppm) met the environmental standard.•The RSE in Co0.70Fe0.30WO4/PMS system for SMX degradation were 23.5%. Bimetal-based catalysts have great renown for peroxymonosulfate (PMS) activation to remove organic pollutant in wastewater, but the catalogue of highly efficient bimetal-based PMS activators is limited. Herein, a series of Co-Fe based tungstate CoxFe1-xWO4 nanomaterials were deployed as brand-new PMS activators, of which the Co-Fe synergism for elevating the catalytic performance towards the sulfamethoxazole degradation was fully investigated. The screened-out Co0.70Fe0.30WO4 nanocatalyst exhibited the best performance of degrading SMX at pH = 7 and T = 25 °C among the other developed counterparts. The Co-Fe synergy in Co0.70Fe0.30WO4/PMS system was elucidated, and the relationship between surface elemental composition and their catalytic activities were examined. Furthermore, detailed reaction parameters in Co0.70Fe0.30WO4/PMS system were investigated. Finally, the stability test results displayed that the Co0.70Fe0.30WO4 can still maintain high activity after four cycles, and the leaching level of cobalt ions (0.83 ppm) in the system met the environmental standard. This work opens novel avenue for developing highly efficient PMS activator.