Synthesis of Zinc Bismuthate Nanorods and Electrochemical Performance for Sensitive Determination of L-Cysteine

Abstract

Zinc bismuthate nanorods with single crystalline cubic ZnBi38O58 phase have been synthesized by a simple hydrothermal process using zinc acetate and sodium bismuthate without any additives. Electron microscopy images show the nanorods have the length and diameter of 2–10 μm and 40–250 nm, respectively. The growth of the zinc bismuthate nanorods has been proposed as a nucleation and crystalline growth process based on the structure and morphology of the products obtained from different hydrothermal conditions. Zinc bismuthate nanorods modified glassy carbon electrode (GCE) has been prepared and used for the electrochemical determination of L-cysteine. A pair of semi-reversible redox peaks located at −0.07 V and −0.52 V are observed at the nanorods modified GCE in KCl solution and the electrode process is diffusion controlled. The intensities of the CV peaks increase obviously with increasing L-cysteine concentration and scan rate. There is a linear relationship between the peak current and concentration of 0.0001–2 mM. The detection limit is 0.074 μM (based on the signal-to-noise ratio of 3) with a correlation coefficient of 0.996. The nanorods modified GCE shows good stability and reproducibility.