Synthesis of EDTA-assisted CeVO₄nanorods as robust peroxidase mimics towards colorimetric detection of H₂O₂

Abstract

In this paper, CeVO₄ materials were developed as highly efficient biomimetic catalysts for the first time to detect H₂O₂. These CeVO₄ materials were prepared by a facile hydrothermal method with the assistance of EDTA, exhibiting different morphologies, surface properties, and distinct peroxidase mimetic activities. Among them, CeVO₄-2 nanorods (NRs) were proved to display the best intrinsic peroxidase-like property compared to other CeVO₄ samples due to their more negative potential and larger BET specific surface area, which could efficiently catalyze the oxidation of 3,3',5,5'-tetramethylbenzidine (TMB) in the presence of H₂O₂ to generate a blue oxide. Based on the excellent peroxidase mimetic catalytic activity of CeVO₄-2 NRs, a simple, convenient and visual H₂O₂ detection system was successfully established. The detection limit of H₂O₂ could reach as low as 0.07 μM. Moreover, the CeVO₄-2 NR-based assay system presented an excellent selectivity, practicability, long-term stability, and reusability. The peroxidase-like catalytic mechanism of CeVO₄-2 NRs was proposed on the basis of active species trapping experiments. This work provides a novel, convenient, rapid, and ultrasensitive system for the colorimetric detection of H₂O₂, which has a bright prospect in H₂O₂ detection and biomedical analysis.