Co/N co-doped porous carbon as a catalyst for the degradation of RhB by efficient activation of peroxymonosulfate

Abstract

We report on the preparation of Co/N-NPC_x/y with porous structure and excellent activation properties. The synthesis involves the preparation of Zn/Co-ZIF_x and the carbonization of Zn/Co-ZIF_x at a high temperature in an inert atmosphere. The volatilization of zinc during carbonization results in a porous structure, which is beneficial to the migration of pollutants. The sizes, specific surface areas, and pore size distribution of Co/N-NPC_x/y can be achieved by tuning Zn/Co ratio. The calcination temperatures mainly affect the crystalline phase, crystallinity, and magnetic properties of the as-prepared materials. The effects of the as-prepared materials properties and activation conditions on the Rhodamine B (RhB) degradation by PMS activation were investigated. Overall, it exhibited superior catalytic activity in PMS activation, as evidenced by almost complete removal of RhB (0.020 mM, 100 mL) by using 5 mg/L Co/N-NPC_0.5/900 and 1.250 mM PMS within 30 min. Furthermore, it confirmed the participation of SO₄^•-, •OH, and ¹O₂ in the catalytic reaction, and both SO₄^•- and ¹O₂ were the main reactive oxygen species that play a major role.

Keywords: Activation performance; Co/N co-doping carbon materials; Degradation; Peroxymonosulfate; Reactive oxygen species; Rhodamine B.