Characteristics of Pt/Nafion® electrodes prepared by a Takenata–Torikai method in sensing hydrogen

The influences of reductant concentration and Pt loading on the response and the recovery time and the sensitivity of the Pt/Nafion® electrodes prepared by a Takenata–Torikai method in detecting hydrogen were investigated in this study. The sensitivities of Pt/Nafion® electrodes prepared in 0.06 N NaBH4 increase non-linearly from 0.0332 to 0.152 μA/cm2 ppm with increasing Pt loadings from 2.59 to 7.76 mg/cm2 in the H2 concentration range of 0–152542 ppm. However, the sensitivities per unit Pt loading show a maximum at Pt loading of 5.20 mg/cm2. Meanwhile, the Pt/Nafion® electrodes with Pt loading of 7.76 mg/cm2 obtained at 0.06 N NaBH4, show the fastest response and recovery speed in sensing hydrogen. Generally, both the response and the recovery time decrease with an increasing of the hydrogen concentration. A sensing model was also proposed to illustrate the sensing phenomenon.