B-Doping Induced Formation of Ultrafine Co Nanoparticles for Highly Sensitive Non-Enzymatic Glucose Sensing

Graphical The doping of B induced the formation of ultrafine Co nanoparticles and realized highly sensitivity non-enzymatic glucose sensing. Doping is one of the effective methods to improve the performance of sensors. Here, we reported that B-doping can induce the formation of ultrafine Co nanoparticles for realizing highly sensitivity non-enzymatic glucose sensing. Co/NC and Co/BNC were prepared by ion exchange and pyrolysis methods. It is interesting to find that B doping can achieve spatial isolation and prevent metal aggregation during MOF pyrolysis. This made the particle size of Co nanoparticles smaller and more uniform, which enriches the active site and thus improves the sensing performance for glucose. The electrochemical results indicate that Co/BNC exhibits strong electrocatalytic activity toward glucose oxidation and the non-enzymatic sensor based on Co/BNC shows excellent performance for glucose analysis with a wide linear range of 0.4 μM–0.522 mM, a high sensitivity of 1064.3 μA mM −1 cm −2 and a low detection limit of 0.08 μM (S/N=3). Therefore, this study demonstrated Co/BNC as a promising glucose sensing material and also provided a novel strategy for improving electrochemical sensing performance through doping.