Shaddock peel-loaded CeO₂ composites with peroxidase-like activity for dye degradation and trace detection of ascorbic acid

Highly efficient and low-cost materials for the degradation of organic dyes in wastewater remain the focus of environmental protection and water pollution control, in which, nanozymes have been at the forefront for the development of a new platform and aroused more and more attention. In this work, a nanoceria@shaddock peel-derived nanocomposite (Ce@CSP) with excellent peroxidase-like performance in methyl violet (MV) degradation as well as ascorbic acid (AA) detection was synthesized by a simple one step in situ pyrolysis of cerium ammonium nitrate (Ce(NH4)(2)(NO3)(6)) and pretreated shaddock peel. By means of the cooperative-reinforcing peroxidase-like activity of the porous carbon material originating from shaddock peel (CSP) and the loaded CeO2 nanoparticle, the obtained nanozyme Ce@CSP displayed a superior catalytic ability in the catalyzed oxidation of the chromogenic substrate 3,3 ',5,5 '-tetramethylbenzidine (TMB) in the presence of H2O2. Specifically, a synergetic absorbent property was also demonstrated by the porous carbon material, bringing the target molecules in close proximity to the nanozyme catalyst and therefore enabling effective decoloration of MV and colorimetric detection of AA with a linear range of 1.6-17.3 mu M and a detection limit of 1.07 mu M. The current work has realized effective decoloration of MV in real water samples and provided a wide range of potential applications of low-cost and eco-friendly materials in organic dye treatment.