Highly sensitive nonenzymetic glucose sensing platform based on MOF-derived multivalent Cu/Cu2O/CuO/C nanocomposites

The redox properties of electrode materials play a vital role in electrochemical performance. Fabrication of electrode materials with multiple oxidation species is highly desired for ultrasensitive glucose sensing. Herein, multivalent Cu/Cu 2 O/CuO/C (Cu/C) nanocomposites were successfully prepared for non-enzymatic glucose sensing by in situ pyrolysis of Cu metal-organic framework (Cu 3 (BTC) 2 ·3H 2 O, Cu-BTC) at a critical temperature. Structure characterizations showed that the nanocomposites maintained the original morphology of Cu-BTC crystals and exhibited mesoporous structures. Meanwhile, multiple Cu species containing Cu, Cu 2 O and CuO were generated simultaneously, which were tightly pinned on the ligand-derived carbon layers. Thus, under the synergistic effect of multivalent Cu species, mesoporous structure and intense interface contact, the sensing platforms based on Cu/C nanocomposites exhibited good glucose detection performance with a wide linear range of 0.005-2.0 mM, ultrasensitivity of 147.65 μA mM -1 cm -2 , low detection limit of 6.31 μM (S/N = 3), and favorable anti-interference properties and stability. Especially, the Cu/C sensing platform showed excellent recoveries of glucose when used to monitor glucose in real sample of honey. The good electrochemical activities of Cu/C nanocomposites render them promising candidates for sensors and other applications. Graphical abstract