Amorphous Ni–Co–Fe hydroxide nanospheres for the highly sensitive and selective non-enzymatic glucose sensor applications

Abstract

Among the numerous non-enzymatic sensors, transition metal or mixed-metal compounds have received considerable attention as promising electrode materials for glucose electrochemical sensors with low-cost and abundance in earth. Most researches on binary and ternary mixed metal compounds have so for been focused on the crystalline rather than the amorphous phase. In this contribution, amorphous Ni–Co–Fe hydroxide nanospheres with a homogeneous distribution of metals are fabricated directly on a graphite substrate by a novel electrochemical deposition method. The as-synthesized amorphous Ni–Co–Fe hydroxide nanosphere as an active sensing material for non-enzymatic glucose sensor exhibits a superior bio-sensing performance toward glucose oxidation with high sensitivity (1860 μA·mM−1cm−2), wide linear range (0.00025–1 mM and 1-5 mM), low detection limit (98 nM), good long-term stability and excellent selectivity in alkaline solutions. This finding greatly promotes the application of amorphous Ni–Co–Fe hydroxide nanostructures as advanced glucose electrochemical sensors materials.