Hierarchically porous NiCo2S4 nanowires anchored on flexible electrospun graphitic nanofiber for high-performance glucose biosensing

Abstract

Nickel cobalt sulfide (NiCo2S4) nanomaterials has attracted much attention in various fields due to its highly catalytic property and low cost. Herein, NiCo2S4 nanowire arrays grown on electrospun graphitic nanofiber film (NiCo2S4/EGF) is prepared for nonenzymatic glucose sensor. A three-dimensional, self-supporting and porous NiCo2S4/EGF is synthesized through a two-step hydrothermal process. By rationally controlling the growth kinetics, NiCo2S4 arrays exhibit a unique core-shell structure with rough surface, providing abundant electrochemically active sites exposed to the electrolyte. When applied to glucose determination, NiCo2S4/EGF modified electrode displays a wide linear range (0.0005–3.571 mM, R2 = 0.995) and low detection limit (0.167 μM, S/N = 3). The excellent sensing properties of NiCo2S4/EGF may be attributed to the high electrocatalytic activity of NiCo2S4 and the good electrical conductivity of EGF frameworks. In addition, the as-proposed sensor also displays other outstanding advantages, including simple preparation, low cost, perfect reproducibility and good selectivity. The results suggest that NiCo2S4/EGF may show great promising in practical applications for glucose detection.