Ni0.31Co0.69S2 nanoparticles uniformly anchored on a porous reduced graphene oxide framework for a high-performance non-enzymatic glucose sensor

Ni0.31Co0.69S2 nanoparticle/reduced graphene oxide (Ni0.31Co0.69S2/rGO) composites have been synthesized via hydrothermal method, and then applied as the active materials for a high-performance non-enzymatic glucose sensor. Field emission scanning electron microscopy (FESEM) and transmission electron microscopy (TEM) were employed to characterize the morphology of the as-prepared samples. The results revealed that the abundant nanoparticles with the size of about 150 nm uniformly anchored on the reduced graphene oxide nanosheets, which are interconnected to form a porous graphene framework. The subsequent electrochemical measurements and kinetic analysis showed that the Ni0.31Co0.69S2/rGO composites possessed excellent electrocatalytic activity to glucose oxidation with a low detection limit of 0.078 mu M and wide linear ranges of 0.001-5 mM and 5-16 mM. Moreover, the sensitivities for two linear ranges are 1753 mu A mM(-1) cm(-2) and 954.7 mu A mM(-1) cm(-2), respectively. In addition, the favorable selectivity, long-term stability and superior practical application were also obtained. All these results indicate that the Ni0.31Co0.69S2/rGO composites are a promising active material for non-enzymatic glucose sensors.