CuO nanosheet as a recyclable Fenton-like catalyst prepared from simulated Cu(ii) waste effluents by alkaline H2O2 reaction

Abstract

The direct discharge of copper containing wastewater into the water body not only causes serious harm to the ecological environment, but also results in copper resource wastage. A green approach was successfully developed to prepare CuO nanosheets (NSs) from simulated Cu(II) waste effluents by alkaline H₂O₂ reaction. The FTIR, EXAFS and XPS results revealed that peroxide group exists on the surface of the as-prepared CuO nanosheets, and the formation mechanism of copper peroxide has been proposed. Assisted by visible light irradiation, the CuO NS as a recyclable Fenton-like catalyst achieved complete degradation of phenol within 40 min. Moreover, the copper ions leached during the Fenton-like process were recycled via alkaline H₂O₂ reaction and their concentration in the solution reduced to below 1 mg L⁻¹, therefore realizing a copper life cycle and Fenton-like degradation of organic pollutants.