Development of Hybrid Membranes Nafion-ZrO₂ for PEM Fuel Cells

Abstract

A hybrid membrane was synthesized by the sol-gel process using Nafion as a polymeric matrix, modified with 1% wt. of ZrO2 (N-ZrO2), the obtained membrane has a thickness of 160 μm. The proton conductivity was evaluated by four-electrode method, with relative humidity and temperature established at 50-100 % and 30-100 ˚C respectively. The hybrid membrane was compared to Nafion 115 (127 µm). The N-ZrO2 showed a proton conductivity of 0.05 S/cm (30 °C, 100 % RH), while the proton conductivity of Nafion 115 is 0.07 S/cm (30 °C, 100 % RH). First results showed a promising performance of the N-ZrO2 membrane for PEM Fuel Cells application at high temperature and low relative humidity. PEMFC performance was determined at temperatures of 30 and 100 ˚C and relative humidity of 50 and 100%, and in electrochemical hydrogen compression at 30 ˚C with a saturated gas flow of 120 ml/min.

Amperometric Glucose Biosensor Electrode Modified with Carbon Nanotubes

“…In order to use CNT for the preparation of electrochemical sensors it is necessary to solve the problem of their insolubility or poor solubility in common solvents. Different strategies have been proposed in this sense, dispersion in dimethyl formamide (15): sodium dodecyl sulphate (16), nafion (naf) (17,18), poliethylimine (PEI) (19,20), polylysine (21), chitosan (22), poly(acryl acid) (23), poly(styrene sulfonic acid) (25), polydiallyldimethylammonium (PDDA) (24) and mineral oil (25)(26)(27)(28).…”

“…Nafion has been already used for dispersing CNT (17)(18)(19), although a systematic study about the influence of the concentration of the nafion solution employed for preparing the dispersions on the performance of the resulting electrodes, has not been reported. In this work we present a determinant study about the influence of the nafion concentration in the solution used to disperse the CNT.…”