Hierarchical flower-like NiO hollow microspheres for non-enzymatic glucose sensors

Hierarchical flower-like NiO hollow microspheres were controllably prepared by a facile hydrothermal method using carbon spheres as the template. Their structure and properties for non-enzymatic glucose sensors were investigated. The results showed that the hierarchical flower-like NiO hollow microspheres are composed of the interconnecting porous NiO nanoplates and each nanoplate is assembled by NiO nanoparticles with the length of about 12.5 nm and the width of about 10 nm. Furthermore, the hierarchical flower-like NiO hollow microspheres obtained at different temperatures were analyzed with the electro-catalytic activity toward the oxidation of glucose in alkaline solution, and the glucose sensor with hierarchical flower-like NiO hollow microspheres obtained at 550 °C exhibits the best performance with the linear range of 5 μM–364 μM and sensitivity of 288.87 mA mM− 1 cm− 2. The sensor is also used for detection of glucose with a relative concentration ranging from 2.96 mM to 7.46 mM and sensitivity of 37.82 mA mM− 1 cm− 2. More importantly, long-term stability and favorable anti-interference were obtained as a result of the hierarchical hollow structure.