fast and clean dielectric barrier discharge plasma functionalization of carbon nanotubes decorated by electrodeposited nickel oxide: application to glucose biosensors

Multiwalled carbon nanotubes (mwcnts) were functionalized using a dielectric barrier discharge plasma in presence of h2osaturated air at 70˚c and atmospheric pressure. the functionalized mwcnts (fcnts) were decorated with electrochemically deposited 10 nm nio nanoparticles, followed by immobilization of glucose oxidase (gox) and the modified electrode was utilized for electrochemical detection of glucose. tem, fesem, tpd and xps techniques were used to characterize the nio/fcnts samples. the maximum amount of oxygenated functional groups such as carbonyl, hydroxyl and carboxylic groups was formed at the plasma exposure time of 4 min. the optimum chronoamperometric deposition time of nio was 3 min. the presence of gox on the nio/fcnts electrode displayed a quasireversible and surfacecontrolled redox wave around −0.52 v with a peak to peak separation of 0.05 v. the gox/nio/fcnts electrode showed a linear performance in the range of 0.23.8 mm glucose with detection limit of 93.0 µm and sensitivity of 2.16 µ.m.