Preparing Co3O4 urchin-like hollow microspheres self-supporting architecture for improved glucose biosensing performance

A new Co3O4 electrode material with self-supporting urchin-like hollow microspheres structure was fabricated via a self-assembly method. Incorporating the adsorption and entrapment, the high porosity and large surface area were favorable for the highly effective immobilization of glucose oxidases. Multiple responses, consisting of enzymatic and material catalysis, were subsequently employed and achieved on the microsphere surface. As the radially oriented nanowires array provided a vast number of catalytic active sites, which lowered the energy barrier of glucose redox and acted as a media to boost the electron transfer, the detection potential was largely decreased. Furthermore, numerous electron transport paths in a short distance were formed among the interconnected bridge-like nanowires, resulting in improved electron transfer efficiency. The prepared glucose biosensor exhibited extra high sensitivity (102.77 μA mM−1 cm−2), fast response (3 s) and outstanding selectivity and stability at a lower applied potential (0.35 V).