Self-assembly of dandelion-like NiCo₂O₄ hierarchical microspheres for non-enzymatic glucose sensor

ABSTRACT

The dandelion-like NiCo₂O₄ hierarchical microspheres were successfully prepared and used as the nonenzymatic glucose sensing materials. The characterization showed that the as prepared hierarchical dandelion-like NiCo₂O₄ microspheres are composed of closely connected outstretched nanowires with the average diameter about 50 nm and length about 1–1.5 μm with the substructured nanowires made up of nanoparticles with the diameters less than 10 nm. The dandelion-like NiCo₂O₄ hierarchical microspheres exhibited superior electrochemical activity towards oxidation of glucose, which is much higher than that of pure NiO microspheres. The amperometric responses are linear with glucose in the concentration range of 10–10480 μM a sensitivity of 430.86 μA cm⁻² mM⁻¹. Moreover, the interference from the commonly interfering species such as L-valine, urea, L-proline, NaCl and L-lysine can be effectively avoided. The good electrochemical performance of materials may be due to its complex chemical compositions, hierarchical structure and the synergetic effect of both individual components. The high sensitivity, wide glucose detection range and good selectivity indicated that the newly developed sensor based on the dandelion-like NiCo₂O₄ hierarchical microspheres is a promising sensor for practical application.

KEYWORDS:

• NiCo₂O₄
• microspheres
• nonenzymatic
• glucose sensor

Funding

This work is financially supported by the National Nature Science Foundation of China (No. 41271249), Educational Commission of Zhejiang Province (No.Y201329269) and National Nature Science Foundation of Zhejiang Province (No. LY12B07001).