Oversized macroporous flower-like Cu9S8 used as an efficient peroxidase mimetic enzyme for the degradation of organic dyes

Abstract

The development of a high-efficiency and stable heterogeneous catalyst has great significance for the recycling treatment of printing and dyeing wastewater. The flower-like Cu9S8 with super large macroporous (d = 133.78 nm) was prepared using porous CuO that was synthesized by the sacrificial template method. The peroxidase mimics activity of flower-like Cu9S8 was determined by catalytic oxidation of 3,3′,5,5′-tetramethylbenzidine (TMB) with H2O2. The kinetic constants (Km = 0.449 mM) displayed that the flower-like Cu9S8 showed excellent affinity to H2O2, which was 8 times lower than that of horseradish peroxidase (HRP). The results of degradation experiments on different kinds of organic dyes showed that the Cu9S8 had a wide application range in the degradation of different dyes with the degradation rate over 98%, and the removal rate of total organic carbon reached 78.2%. The flower-like Cu9S8 can be a candidate catalyzer in the field of printing and dyeing wastewater treatment due to its high catalytic cycle stability and wide pH application range (3.0–8.0).