Architecture of bimetallic-MOF/silicate derived Co/NC@mSiO2 as peroxymonosulfate activator for highly efficient ciprofloxacin degradation

Abstract

Bimetallic-ZIF@silicate derived Co/NC@mSiO2 hollow sphere was developed as an excellent peroxymonosulfate (PMS) activator for ciprofloxacin (CFL) antibiotic and parabens degradation. First, bimetallic Zn-Co/ZIF frameworks were prepared by a solvothermal method and then coated with a silica layer. Subsequently, Zn-Co/ZIF@mSiO2 was carbonized under nitrogen gas to obtain the Co, N co-doped porous carbon material. The evaporation of zinc metal in Zn-Co/ZIF@mSiO2 by inert gas flow played an important role in the formation of porous carbon material. In the presence of a small quantity of PMS, this hollow sphere material acts as a highly efficient catalyst for the degradation of CFL with a rate constant of 0.07 min−1. The findings obtained from the quenching radical test and electron paramagnetic resonance (EPR) reveal that Co site within the hollow sphere nanoreactor catalyzed PMS to the generation of the HO, SO4−, and 1O2 for CFL degradation. Notably, the presence of Co NPs in the hollow sphere material enables the facile separation of the catalyst from the reaction mixtures using an external magnet. Furthermore, the as-prepared catalysts exhibited antibacterial activity in Staphylococcus aureus (S. aureus). The current study provides new horizons to develop ZIF-derived hybrid hollow materials in eliminating organic pollutants.