Co–Cu–Al Layered Double Oxides as Heterogeneous Catalyst for Enhanced Degradation of Organic Pollutants in Wastewater by Activating Peroxymonosulfate: Performance and Synergistic Effect

Abstract

In order to exploit Co–Cu synergistic effect to develop catalyst with high activity, CoCuAl-layered double oxides was synthesized from CoCuAl-layered double hydroxides. The prepared CoCuAl-LDOs possessed high purity, uniform morphology, and a large special surface area (103.8 m2/g). CoCuAl-LDOs is an efficient catalyst for activating peroxymonosulfate (PMS) to degrade organic pollutants. Acid orange 7 (AO7, 20 mg/L) can be completely degraded within 30 min using 0.1 g/L CoCuAl-LDOs and 0.1 g/L PMS. The CoCuAl-LDOs/PMS system also exhibited good performance over a wide pH range. SO4•– was identified as the main reactive species responsible for pollutant degradation. More importantly, the structure–property relationship was investigated by H2-TPR and XPS. It was found that the high performance of CoCuAl-LDOs is attributed to the Co–Cu synergistic effect which can accelerate the redox cycle of Co2+/Co3+. This study sheds light on the Co–Cu synergistic effect for developing catalyst with high performance toward activating PMS in environmental remediation.