Facile Sol-Gel Fabrication of Cu/N-P-doped C Nanocatalysts for Peroxymonosulfate Activation Towards Advanced Oxidation of 4-Nitrophenol

Designing of heterogeneous catalysts is very important for activating peroxymonosulfate (PMS) in oxidative degradation of organic pollutants. In this work, Cu/N-P-doped C (Cu/N-P-C) was synthesized by a sol-gel method where the precursor was calcined in a N2 atmosphere. The Cu/N-P-C prepared at 700(degrees)C could activate PMS in oxidative degradation of 4-nitrophenol (4-NP) where 99.17% of 4-NP could be degraded in 4 minutes. The effects of the concentration of 4-NP, solution pH value, PMS dose, and catalyst dosage on the degradation of 4-NP were investigated, and the optimum pH value was determined to be 9. Electron paramagnetic resonance (EPR) and free radical quenching experiments showed that 1O2 was the primary reactive species, and SO4- and OH also contributed to the oxidation reaction, and a possible mechanism for this degradation was presented. The catalyst can be used five times in this oxidation system. Our study provides useful suggestions for designing catalysts with desirable activity.