Reusable hydrazine amperometric sensor based on Nafion®-coated TiO2-carbon nanotube modified electrode

The preparation of electrodes chemically modified with a new nanocomposite material obtained by titanium oxide (TiO2) nanoparticle deposition on thiolated carbon nanotube (CNT) surfaces was investigated. The transmission electron microscopy (TEM) and X-ray diffraction (XRD) results indicated that the anatase TiO2 nanoparticles of 4.4 nm average particle size were supported on the surface of the CNTs. The electrochemical sensing properties and stability of a Nafion®-coated TiO2-CNT were evaluated by amperometric measurement. The modified electrode exhibited a 0.35-162 μM linear response to hydrazine and a 0.22 μM detection limit. The relative standard deviation over the course of 14 repetitive measurements was 3.8%. Moreover, the amperometric currents were very stable in the presence of interfering species. The overall results served to establish that this modified electrode can be effectively employed as a reusable low-detection-limit, good-anti-interference hydrazine sensor.