Excellent performance of mesoporous Co3O4/MnO2 nanoparticles in heterogeneous activation of peroxymonosulfate for phenol degradation in aqueous solutions

► Mesoporous MnO 2 exhibited activity in peroxymonosulfate (PMS) activation. ► Co/MnO 2 nanoparticles presented better performance than Co 2+ /PMS in phenol degradation. ► Phenol degradation on Co/MnO 2 followed first order kinetics. Mesoporous α-MnO 2 and its supported Co 3 O 4 nanoparticles were synthesized, characterized and tested in heterogeneous activation of peroxymonosulfate (PMS) for phenol degradation in aqueous solution. α-MnO 2 supported Co 3 O 4 presented as nanorod particles and showed H 2 redox reduction at low temperature. Bulk α-MnO 2 and Co 3 O 4 could activate peroxymonosulfate to generate sulfate radicals for phenol degradation but at low activity. Co 3 O 4 /MnO 2 nanoparticles exhibited much high activity in peroxymonosulfate activation for phenol degradation with 100% conversion in 20 min and 3 wt% is the optimum Co loading. Phenol degradation followed a first order kinetics. Stability tests also showed that Co 3 O 4 /MnO 2 presented stable performance in phenol degradation in several runs.