Assembly of ultrathin NiOOH nanosheets on electrochemically pretreated glassy carbon electrode for electrocatalytic oxidation of glucose and methanol

The aqueous NiOOH nanosheets were synthesized using a hydrothermal method via a surfactant template under mild reaction conditions. The as-prepared products were characterized by atomic force microscopy (AFM), X-ray diffraction (XRD) and scanning electron microscopy (SEM), the results of which indicated that ultrathin and porous NiOOH nanosheets with a thickness of only several nanometers have been obtained. The obtained NiOOH nanosheets were subsequently assembled on electrochemically pretreated glassy carbon (EPGC) electrode through a simple physical bath deposition method to form NiOOH/EPGC electrode. SEM, energy dispersive X-ray spectroscopy (EDX) and electrochemical impedance spectroscopy (EIS) proved the successful assembly of NiOOH on EPGC surface. The effective deposition of NiOOH electrocatalyst on electrode is believed to result from the higher surface area and higher surface concentration of CO functional groups existing on EPGC surface. Glucose and methanol were selected as model molecules to investigate the electrocatalytic performance of NiOOH/EPGC electrode. The electrochemical experiments revealed that a favorable activity of the NiOOH/EPGC electrode toward electrooxidation of glucose and methanol has been found. The present NiOOH/EPGC based amperometric sensor exhibited a rapid and highly sensitive response to glucose and methanol, which might find promising applications in medical applications, biological fuel cells and food industries.