Ni-Based metal-organic framework derived Ni@C nanosheets on a Ni foam substrate as a supersensitive non-enzymatic glucose sensor

Uniform and compact porous Ni@C nanosheet membranes derived from Ni-based metal organic frameworks were successfully anchored on a Ni foam substrate via hydrothermal treatment with successive pyrolysis. The Ni@C/Ni foam was employed as a self-supporting electrode for non-enzymatic glucose sensing and exhibited remarkable electrocatalytic activity. It can be attributed to the hierarchical structure composed of Ni@C nanosheet array membranes freestanding on Ni foam and mesoporous Ni@C nanosheets. An ultrahigh sensitivity of 32.79 mA mM^-1 cm^-2 and a low detection limit of 50 nM were realized, which were superior to some existing glucose sensors. Meanwhile, a reasonable linear range from 0.15 μM to 1.48 mM was achieved. Furthermore, the Ni@C/Ni foam possessed various merits, such as excellent selectivity, good reusability, acceptable reproducibility, satisfying long-term stability and high tolerance to chloride ions. We further demonstrated its practicability by detecting glucose concentrations in human blood serum samples. The results enable the Ni@C/Ni foam to be an attractive candidate for practical application in non-enzymatic glucose sensing.