Development of selective chloroform sensor with transition metal oxide nanoparticle/multi-walled carbon nanotube nanocomposites by modified glassy carbon electrode

Transition metal oxide (NiO) nanoparticles decorated multi-walled carbon nanotubes (NiO/MWCNT nanocomposites, NCs) were prepared by a facile solution method using reducing agents in alkaline medium. The NiO/MWCNT NCs were characterized by UV/vis, FT-IR, energy-dispersive X-ray spectroscopy (XEDS), powder X-ray diffraction (XRD), field-emission scanning electron microscopy (FESEM), and scanning electron microscopy (TEM). The NiO NPs or NiO/MWCNTs were deposited separately on flat glassy carbon electrode (GCE) with conducting binders (5% nafion) to result in a sensor that has a fast response towards selective chloroform (CHCl3). Features including high-sensitivity, lower-detection limit, reliability, reproducibility, ease of integration, long-term stability, selective, and enhanced electrochemical performances are investigated in details. It is detailed studied the sensor performances with NiO NPs/GCE and NiO/MWCNT/GCE electrodes separately and found that NiO/MWCNT/GCE exhibits the higher sensitivity and lower detection limit compared to NiO/GCE assembly. The calibration plot is linear (r(2) = 0.9763) over concentration range (3.5 nM to 35.0 mM) with NiO/MWCNT/GCE. The sensitivity and detection limit was calculated for NiO/MWCNT/GCE as similar to 917.7 nA/cm(2) mu M and 0.1034 +/- 0.0002 nM (at a signal-to-noise-ratio, SNR of 3) respectively. Finally, the efficiency of the proposed chemi-sensors can be applied and effectively utilized for the detection of toxic chloroform compound in environmental and healthcare fields in broad scales. (C) 2016 Taiwan Institute of Chemical Engineers. Published by Elsevier B.V. All rights reserved.