Preparation of high-quality palladium nanocubes heavily deposited on nitrogen-doped graphene nanocomposites and their application for enhanced electrochemical sensing.
A nanocomposite of high-quality palladium nanocubes (PdNCs) decorated nitrogen-doped graphene (NGE/PdNC) was successfully prepared by using bromide ion as a capping agent and polyvinyl pyrrolidone as a stabilizer. The morphology and composition of NGE/PdNC nanocomposites were characterized by field emission-scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), energy-dispersive X-ray spectroscopy (EDS), X-ray powder diffraction (XRD) and Raman spectra. To explore the application of NGE/PdNC nanocomposites in electrochemistry, the electrocatalytic response to nitrite at a NGE/PdNC-based electrode was investigated. Thus, a highly sensitive and selective electrochemical sensor for the detection of nitrite was constructed based on a glassy carbon electrode modified with the NGE/PdNC nanocomposites. The electrochemical behavior of this nanocomposites was studied by electrochemical impedance spectroscopy, cyclic voltammetry and chronoamperometry. The electrochemical investigations proved that the NGE/PdNC nanocomposites exhibited good electrocatalytic performance for the oxidation of nitrite, including a wide linear range from 5.0×10-7to 1.51×10-3molL-1, a high sensitivity of 342.4μAmM-1cm-2and a low detection limit of 0.11μmolL-1at the signal-to-noise ratio of 3 (S/N=3). This non-enzymatic sensor also showed a good reproducibility and stability. The obtained NGE/PdNC nanocomposites may be a potential composite for applying in the field of other electrochemical sensing, catalysis and optics.
Institute of Analytical Science, Shaanxi Provincial Key Laboratory of Electroanalytical Chemistry, Northwest University, Xi'an, Shaanxi 710069, China.
Yu
Y
Shen
Institute of Analytical Science, Shaanxi Provincial Key Laboratory of Electroanalytical Chemistry, Northwest University, Xi'an, Shaanxi 710069, China.
Dejiang
D
Rao
Institute of Analytical Science, Shaanxi Provincial Key Laboratory of Electroanalytical Chemistry, Northwest University, Xi'an, Shaanxi 710069, China.
Wushuang
W
Bai
Institute of Analytical Science, Shaanxi Provincial Key Laboratory of Electroanalytical Chemistry, Northwest University, Xi'an, Shaanxi 710069, China.
Qinglin
Q
Sheng
Institute of Analytical Science, Shaanxi Provincial Key Laboratory of Electroanalytical Chemistry, Northwest University, Xi'an, Shaanxi 710069, China. Electronic address: zhengjb@nwu.edu.cn.
Jianbin
J
Zheng
Electrocatalysis; Electrochemical sensor; Nitrite; Nitrogen-doped graphene; Palladium nanocubes