Plant root nodule like nickel-oxide–multi-walled carbon nanotube composites for non-enzymatic glucose sensors

Herein, in this work we synthesized plant root nodule like NiO–MWCNT nanocomposites by a simple, rapid and solvent-free method using nickel formate as a precursor. Using a first-principle simulation study the interactions and charge transfer behaviour of the NiO and MWCNT composite is investigated. The as-prepared NiO–MWCNT composite is employed to fabricate a modified non-enzymatic carbon paste electrode (CPE) for glucose sensing. From the electrochemical investigation, the fabricated sensor shows an excellent sensitivity of 6527 μA mM −1 cm −2 with a detection limit of 19 μM and a linear response over a range from 0.001 mM to 14 mM of glucose concentrations, at an applied potential of 0.5 V. Importantly the sensor also exhibits greater stability, selectivity and reproducibility. A first principle simulation study shows the differences in charge density and charge transfer behaviour from nanotubes to NiO nanoparticles, which in turn enhances the electro catalytic property of the NiO–MWCNT composite. Hence, these results indicate that the NiO–MWCNT composite is a potential material for non-enzymatic electrochemical glucose sensors.