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 mu A mM(-1) cm(-2) with a detection limit of 19 mu M 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.