Preparation of Fe3O4/MWCNT nano-hybrid and its application as phenol sensor

Abstract

In this work, Fe3O4/MWCNT nano-hybrid was successfully fabricated. Its composition, structure and morphology were characterized by XRD and TEM and the results suggested that Fe3O4 nanoparticles with cubic structure was smoothly dispersed on MWCNT surface. Electrochemical impedance spectra (EIS) showed that Fe3O4/MWCNT presented excellent electron transfer behavior. The electrochemical determination of phenol in phosphate buffer solution (pH 7.4) revealed that Fe3O4/MWCNT modified GC electrode (Fe3O4/MWCNT/GCE) exhibited superior catalytic activity toward phenol with a linear equation of ipa (μA) = −0.018 − 0.034c (μmol/L) R = 0.9990 in a wide range from 5 to 235 μM. The detection limit was calculated to be 4.83 μM (S/N = 3) and a high sensitivity of 481.2 μA mM−1 cm−2 was achieved from the equation slope. This electrocatalyst also showed a short response time and high anti-interference to ethanol. The wide detection range, fast response, low detection limit, high sensitivity and anti-interferance of Fe3O4/MWCNT endowed it with potential application in electrochemical detection of phenol.