Defect Surface Engineering of Hollow NiCoS Nanoprisms towards Performance-Enhanced Non-Enzymatic Glucose Oxidation.

Transition metal sulfides have been explored as electrode materials for non-enzymatic detection. In this work, we investigated the effects of phosphorus doping on the electrochemical performances of NiCoS electrodes (P-NiCoS) towards glucose oxidation. The fabricated non-enzymatic biosensor displayed better sensing performances than pristine NiCoS, with a good sensitivity of 250 µA mM cm, a low detection limit (LOD) of 0.46 µM (S/N = 3), a wide linear range of 0.001 to 5.2 mM, and high selectivity. Moreover, P-NiCoS demonstrated its feasibility for glucose determination for practical sample testing. This is due to the fact that the synergetic effects between Ni and Co species, and the partial substitution of S vacancies with P can help to increase electronic conductivity, enrich binary electroactive sites, and facilitate surface electroactivity. Thus, it is found that the incorporation of dopants into NiCoS is an effective strategy to improve the electrochemical activity of host materials.