Synthesis of feather-like CeO2 microstructures and enzymatic electrochemical catalysis for trichloroacetic acid

Abstract

Novel feather-like CeO2 microstructures were achieved by a thermal decomposition approach of Ce(OH)CO3 precursor. The Ce(OH)CO3 was obtained from a solvothermal method employing Ce(NO3)3.6H2O with C6H[Formula: see text]N4 and C[Formula: see text]H[Formula: see text](CH3)3NBr (CTAB) at 190[Formula: see text]C in a water–PEG-200 mixed solution. The feather-like CeO2 dendrite was obtained by thermal conversion of the feather-like Ce(OH)CO3 at 650[Formula: see text]C in air. A reasonable growth mechanism was proposed with the soft-template effect of PEG-200. The electrochemical behavior and enzyme activity of myoglobin (Mb) immobilized on CeO2–Nafion modified glassy carbon electrode (GCE) are demonstrated by cyclic voltammetric measurements. The results indicate that CeO2 can obviously promote the direct electron transfer between the Mb redox centers and the electrode. The Mb on CeO2–Nafion behaves as an elegant performance on the electrochemical reduction of trichloroacetic acid (TCA) from 0.32[Formula: see text][Formula: see text]M to 2.28[Formula: see text][Formula: see text]M. The detection limit is estimated to be 0.08[Formula: see text][Formula: see text]M.