Annealing temperature regulating the dispersity and composition of nickel-carbon nanoparticles for enhanced glucose sensing

Design of electrodes with both excellent electrocatalytic activity and facile synthesis process is the pivotal challenge in the progress of non-enzymatic glucose sensors. In this work, a series of highly dispersed nickel-carbon nanoparticles modified boron doped diamond composite electrodes were fabricated after the boron doped diamond films with a sputtering nickel layer being annealed at different temperature in hydrogen atmosphere. The surface morphology and interface structure of nickel-carbon nanoparticles modified boron doped diamond samples were characterized detailedly with the increase of annealing temperature. The charge transfer of synthesized electrodes was improved with the increasing content of sp ² carbon and the improvement of crystallinity of nickel. Therefore, the volcano-type electrocatalytic performance trend was observed with the composite electrode prepared after annealing at 500 °C presenting the best glucose sensing performance with the sensitivities of 1730 and 1081 μA cm ⁻² mM ⁻¹ in glucose concentration ranges of 0.01–2.12 and 2.12–9.06 mM respectively and a low detection limit of 0.2 μM (S/N = 3).