Electrodeposition synthesis of reduced graphene oxide-carbon nanotube hybrids on indium tin oxide electrode for simultaneous electrochemical detection of ascorbic acid, dopamine and uric acid

Reduced graphene oxide-carbon nanotube (rGO-CNT) hybrids have been synthesized by electrodeposition of GO stabilized CNT using indium tin oxide (ITO) as working electrode, followed by electrochemical reduction of GO-CNT into rGO-CNT on the surface of ITO. The combined characterizations of scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS) analyses have been used to examine the structure of rGO-CNT hybrids, indicating the successful preparation of hybrids. More importantly, compared with the bare ITO and rGO/ITO electrodes, the rGO-CNT/ITO electrode exhibits excellent sensing performance for electrochemical detection of ascorbic acid (AA), dopamine (DA) and uric acid (UA), leading to a high-performance electrochemical sensor for simultaneous detection of AA, DA and UA. The linear detection ranges of the AA, DA and UA sensors based on rGO-CNT hybrids were estimated to be 10-200 mu M, 0.2-8.0 mu M and 0.2-16.0 mu M, and the detection limits were 5.31 mu M, 0.04 mu M and 0.17 mu M, respectively.