Sensitive detection of hydroquinone using exfoliated graphene-Au/glassy carbon modified electrode.
Nanotechnology
; 29(9): 095501, 2018 Mar 02.
Article
en En
| MEDLINE
| ID: mdl-29260725
ABSTRACT
Graphene nanosheets (EGr) were electrochemically prepared through one-step exfoliation of a graphite rod in a mixture of H2SO4HNO3 (31) at low bias (4 V). Subsequently, gold nanoparticles were attached to the graphene surface (EGr-Au) by the reduction of the metal precursor (HAuCl4) in aqueous solution containing dispersed graphene sheets. According to the XRD investigation, the synthesized material consists of a mixture of few-layer (86%) and multi-layer (14%) graphene. The interlayer distance was found to be in the range of 0.466-0.342 nm, which is larger than the interlayer distance in graphite (0.335 nm). The average size of gold nanoparticles in the EGr-Au sample was 24 nm, in excellent agreement with the TEM results. The synthesized material was then employed to modify a glassy carbon (GC) substrate, in order to obtain a modified electrode (GC/EGr-Au). Next, the electrochemical behavior of hydroquinone (HQ) in the presence and absence of interfering species, catechol (CAT) and bisphenol A (BPA) was studied and the corresponding calibration curves were plotted. Thus, in solutions without interfering species, the GC/EGr-Au electrode has a wide linear range (3 × 10-7-10-4 M), high sensitivity (0.089 A M-1) and low detection limit (LOD = 10-7 M; S/N = 3). The presence of either catechol or bisphenol A leads to the increase of LOD to 2 × 10-7 M, and in addition changes the electrode sensitivity, up to 0.146 A M-1.
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MEDLINE
Tipo de estudio:
Diagnostic_studies
Idioma:
En
Año:
2018
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Article