علی اکبر آشکاران

tIn this study, we report a novel graphene decorated gold nanocage nanocomposite through thermal mod-ification route as a hydrazine sensor. Gold nanocages were synthesized, using the galvanic replacementbetween silver nanocubes and aqueous gold solution. Graphene nanosheets were functionalized by reac-tion with N,N-dimethylformamide (DMF) at relatively high temperature to generate chemically modifiedgraphene (CMG). Surface topography and thickness of CMG nanosheets were obtained by atomic forcemicroscopy (AFM). Ultraviolet visible (UV–vis) spectroscopy, scanning electron microscopy (SEM), fieldemission scanning electron microscopy (FESEM), Fourier transformed infrared spectroscopy (FTIR) andtransmission electron microscopy (TEM) were used to characterize the physicochemical properties ofgold nanocage/CMG nanocomposite. The electrochemical behaviour of sensor was investigated usingcyclic voltammetry (CV), amperometry and electrochemical impedance spectroscopy (EIS). It was foundthat the gold nanocage/CMG modified glassy carbon electrode (GCE) exhibits low oxidation potential(0.17 V) with two linear ranges from 6 M to 30 M and 30 M to 1.7 mM for sensing hydrazine withdetection limit of 0.5 M. The modified electrode exhibits good selectivity for hydrazine amperometricresponse in the presence of common ions and some biological interfering species and it can be easilyprepared which makes it reproducible. Furthermore, the present sensor exhibits high level of stabilityfor the determination of hydrazine.