Simultaneous electrochemical detection of ascorbic acid and dopamine on Cu2O/CuO/electrochemically reduced graphene oxide (CuxO/ERGO)-nanocomposite-modified electrode

This study proposes a new approach for the electrochemical growth of Cu2O/CuO/electrochemically reduced graphene oxide (CuxO/ERGO) nanostructures based on simultaneous co-reduction of both copper ions, i.e. Cu (I) and Cu (II), and graphene oxide from an aqueous suspension on gold electrode. X-ray diffraction (XRD) spectra of the as-prepared CuxO/ERGO electrode show that CuO, Cu2O and graphene structures are composite nanostructures. Scanning electron microscopy (SEM) images show that CuxO/ERGO forms in different shapes (nanoflowers and nanocubes). Experimental results show that structures of CuxO/ERGO nanocomposite films can be easily controlled by application potential and experimental media. The resulting CuxO/ERGO nanocomposite electrodes exhibit good electrocatalytic activity towards dopamine sensing in the presence of ascorbic acid and could be used for biosensor applications [with low working potential (at approximately +0.2 V), high sensitivity (122.4 mu A cm(-2) mM(-1)) and low detection limit (12 x 10(-9) mol.L-1)].