An amperometric ethanol sensor based on a Pd-Ni/SiNWs electrode

A new amperometric ethanol sensor has been developed. The sensor uses the silicon nanowires covered with co-deposited palladium-nickel (Pd-Ni/SiNWs) as the working electrode. The detection of ethanol concentration is based on the response currents resulted from the electro-catalytic oxidation of ethanol. The performance of the sensor was characterized by cyclic voltammetry and fixed potential amperometry techniques. In 1 M KOH solution containing different ethanol concentrations, the sensor shows a good sensitivity of 7.48 mA mM^-1 cm^-2 and the corresponding detection limit (signal-to-noise ratio = 3) of 6 μM for cyclic voltammetry. Meanwhile, it also displays a sensitivity of 0.76 mA mM^-1 cm^-2 and the corresponding detection limit of 10 μM for fixed potential amperometry. The results demonstrate that the Pd-Ni/SiNWs electrodes are potential as the electrochemical integrated sensors for ethanol detection.