NiS Hollow Spheres for High‐Performance Supercapacitors and Non‐Enzymatic Glucose Sensors

α-NiS and β-NiS hollow spheres were successfully synthesized via the Kirkendall effect under different hydrothermal conditions. The obtained α-NiS and β-NiS hollow spheres were evaluated as electrode materials for supercapacitors. Importantly, the α-NiS hollow sphere electrode has a large specific capacitance (562.3 F g(-1) at 0.60 A g(-1)) and good cycling property (maintaining about 97.5% at 2.4 A g(-1) after 1000 cycles). Furthermore, the as-prepared α-NiS and β-NiS hollow spheres were successfully applied to construct electrochemical glucose sensors. Especially, the α-NiS hollow spheres exhibit a good sensitivity (155 μA mM(-1) cm(-2)), low detection limit (0.125 μM), and a wide linear range.