Preparation of amorphous Ni/Co bimetallic nanoparticles to enhance the electrochemical sensing of glucose

Based on the incidence of diabetes, developing glucose sensors of superior performance with low-cost transition metals (TMs) has been the direction of many researchers, amorphous TMs with highly efficient electrocatalytic properties have attracted our interest. On this basis, amorphous nickel-cobalt bimetallic N-doped carbon nanoparticles on carbon cloth (a-Ni2/Co1-NC/CC) were fabricated from ZIF-8, which was then used to fabricate an enzyme-free glucose sensor. It was found that the a-Ni2/Co1-NC/CC had the best response to glucose in 0.4 M NaOH at 0.55 V (vs Hg/HgO). As compared to crystal Ni2/Co1 nanoparticle on carbon cloth (c-Ni2/Co1 NPs/CC), cyclic voltammetry (CV) and chronoamperometry studies revealed that the a-Ni2/Co1-NC/CC showed a signifi-cant increase in the efficient of electrochemical oxidation of glucose under optimal conditions, exhibiting a high sensitivity of 2.455 mA mM-1 cm-2 with a low detection limit of 0.15 mu M (S/N = 3). Furthermore, the con-structed sensor based on a-Ni2/Co1-NC/CC also has long-term stability and can be used to detect glucose accurately in beverages (pure milk, coffee drinks, tea drinks, and soda water) with reasonable recovery from 95.6 % to 105.6 %. This study provides a simple and feasible method for the construction of a highly sensitive non-enzyme glucose electrochemical sensor based on amorphous TMs.