Multi-functional NiO/g-C 3 N 4 hybrid nanostructures for energy storage and sensor applications

A multi-functional NiO/g-C 3 N 4 (NC) hybrid nanostructure was synthesized by a hydrothermal process using melamine and Ni(OH) 2 as precursors followed by thermal treatment. The optimal conditions were determined by studying the process conditions, such as the Ni(OH) 2 to melamine ratio and thermal treatment temperature. The NC prepared in this study exhibited both excellent glucose sensing properties and supercapacitor properties. A very high glucose sensitivity, as high as 5,387.1 µA mM −1 cm −2 , and excellent energy density of 49.6 Wh kg −1 at a power density of 1,064.2 W kg −1 were obtained when NC was used as the electrode material for glucose sensing and symmetric supercapacitor, respectively. A flexible glucose sensing device using a flexible substrate and self-powered glucose sensor system that used the same material (NC) for the both power supply and sensing devices were also demonstrated.