Highly Selective Simultaneous Detection of 1,4-Dihydroxybenzene and 1,2-Dihydroxybenzene Based on CdSe Quantum Dots-Multiwalled Carbon Nanotube Composite

A new electrochemical sensor based on CdSe quantum dots-multiwalled carbon nanotube composite film (CdSeQDs-cMWCNTs) was developed for highly selective simultaneous determination of 1,4-dihydroxybenzene (hydroquinone, HQ) and 1,2-dihydroxybenzene (catechol, CC) in 0.1 M phosphate buffer solution (pH 7.4). CdSeQDscMWCNTs/GCE exhibited two well-distinguished anodic peaks with large currents for simultaneous detection of HQ and CC in comparison with bare GCE and cMWCNTs/GCE. Furthermore, CdSeQDs-cMWCNTs/GCE has an excellent antiinterference ability for the detection of HQ and CC in the presence of some inorganic compounds and phenol derivatives. Under the optimized condition, CdSeQDs-cMWCNTs/GCE showed wide linear responses from 0.5 μM to 110 μM for HQ, and from 0.5 μM to 110 μM for CC, with the detection limits of 0.35 μM and 0.25 μM, respectively. CdSeQDs-cMWCNTs/GCE was successfully applied to the simultaneous determination of HQ and CC in tap water with satisfactory recovery.