Dendritic Cu–Co ₃ O ₄ with Elevated Oxygen Vacancies for the Degradation of Organic Pollutants

Highly dendritic Co3O4 and Cu–Co3O4 composites with increased exposed active sites and abundant oxygen vacancies were synthesized via the hydrolysis of ZIF-67. As a catalyst for bisphenol A elimination, the apparent degradation rate constant in the presence of dendritic Cu–Co3O4 was five times higher than those of the referenced catalysts both with persulfate and with peroxymonosulfate. Moreover, its potential application was demonstrated by the high efficiencies for degrading several organic dyes, tetracycline hydrochloride, and p-nitrophenol. Its robust reusability was also confirmed by the results of successive runs of the degradation test. It was discovered that the singlet oxygen was the major active oxygen species for the destruction of the organic contaminants based on the mechanism experiments. The investigation demonstrated that the highly dendritic structure with various active sites, rich oxygen vacancies, a high amount of Co(II) species, and the synergistic effect of Cu species could be responsible for the robust catalytic activity of Cu–Co3O4 for the degradation reactions.