Spinel sub-stoichiometric CuxCoyO4 nano-wire framework thin-film electrode for enhanced electrochemical non-enzymatic sensing of glucose

Spinel sub-stoichiometric CuxCoyO4 nano-wire framework thin-films were fabricated for the electrochemical glucose biosensors by hydrothermal-annealing process. Developed CuxCoyO4 nano-wire framework thin-films were characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), Brunauer-Emmet-Teller (BET) and scanning electron microscopy (SEM) techniques. The results confirmed well-established nano-wire sub-stoichiometric CuxCoyO4 framework with high specific surface area and abundant electro-active sites and channels for ions transfer. The average CuxCoyO4 nano-wire was similar to 40 nm in diameter and more than 1 mm in length. In electrochemical non-enzymatic biosensor, the CuxCoyO4 electrode has demonstrated superior glucose detection capabilities including high glucose sensitivity of 13291.7 mA mM(-1) cm(-2), one of the fastest response time (less than 0.5 s), excellent selectivity in serum and detection limit as low as 1.36 mM. More importantly, the outstanding electro-catalytic performance and relatively simple synthesis method makes this spinel CuxCoyO4 nano-wire framework promising for sustainable improvement of electrochemical non-enzymatic glucose sensing. (c) 2019 Elsevier Ltd. All rights reserved.