Oxygen vacancy on hollow sphere CuFe2O4 as an efficient Fenton-like catalysis for organic pollutant degradation over a wide pH range

Abstract

Exploitation of highly active, stable and easily recyclable catalytic materials for heterogeneous Fenton-like processes has been enormously stimulated by the globally increased demands for water purification and guarantees of human health. Herein, a novel heterogeneous Fenton-like catalyst, hollow sphere CuFe2O4 with oxygen vacancies (HS-CuFe2O4-σ), was designed to efficiently activate H2O2 with good stability over a wide pH range. Results showed that the pollutant ciprofloxacin (CIP) could be completely removed within 30 min at pH 6.5–9.0. Compared with CuFe2O4, the rate constant of CIP degradation in neutral pH was enhanced by 20 times. Sufficient experimental exploration and density functional theory (DFT) calculations clearly demonstrated that the efficient catalytic performance of HS-CuFe2O4-σ was attributed to the synergistic effect of oxygen vacancies (OVs) and the nanoconfinement of the catalyst’s special hollow structure. This study lays a foundation for the rational design of catalysts that apply heterogeneous Fenton reactions to practical water purification.