Radiolytic Synthesis of Vinyl Polymer-Clay Nanocomposite Membranes for Direct Methanol Fuel Cell

Yoon-Seob Kim,Yun Ok Kang,Seong-Ho Choi

doi:10.1155/2014/562865

Abstract

The three-type vinyl polymer-clay nanocomposite membranes with sulfonate (–SO3Na) are prepared by the solvent casting method after radiation-induced copolymerization for application of the direct methanol fuel cell (DMFC) membrane. The three-type vinyl polymers in polymer-clay nanocomposite membranes are included in poly(styrene-co-sodium styrene sulfonate), poly(St-co-NaSS), poly(2-hydroxyethyl methacrylate-co-NaSS), poly(HEMA-co-NaSS), and poly(acrylic acid-co-NaSS), and poly(AAc-co-NaSS). The proton conductivity (S/cm), water uptake (%), and ion-exchange capacity (meq/g) of the poly(St-co-NaSS)-clay nanocomposite membrane are 0.0779, 32.4, 3.63, respectively. The MeOH permeability of the poly(St-co-NaSS)-clay nanocomposite membrane is exhibited as7.7×10−9 mmol·cm−2·s−1. DMFC performance for poly(St-co-NaSS)-clay nanocomposite membrane is also measured in cell voltage and power density verses current density. As results, the poly(St-co-NaSS)-clay nanocomposite membrane can be used as a DMFC membrane on behalf of the commercial Nafion membrane.

Highlights

Direct methanol fuel cell (DMFC) [1, 2] and polymer electrolyte membranes fuel cell (PEMFC) [3, 4] have recently received much attention due to these power sources presenting a high-energy efficiency and low emission of pollutants
The MeOH permeation causes a loss of fuel and a mixed potential being formed at the cathode leading to a lower electrochemical performance of the DMFC
Vinyl polymer-clay nanocomposite membranes were synthesized by radiation-induced copolymerization of the functional monomers as a one-step reaction

Summary

Introduction

Direct methanol fuel cell (DMFC) [1, 2] and polymer electrolyte membranes fuel cell (PEMFC) [3, 4] have recently received much attention due to these power sources presenting a high-energy efficiency and low emission of pollutants. Lee et al [13] prepared the disulfonated poly(arylene ether sulfone)-silica nanocomposites membrane for DMFC and determined the MeOH permeability as 10−6∼10−7 cm s−1 value at 30∘C. Sulfonated poly(ether ether ketone) (SPEEK) membrane-clay composite membrane was prepared by Jaafar et al [14] and determined methanol permeability with a 10−9∼10−10 cm s−1. Nafionmontmorillonite composite membrane with MeOH permeability of 0.042 mol/L at 1 h for DMFC was prepared by Jung et al [16] little has been reported for the vinyl polymer-clay nanocomposite membrane with low MeOH permeability. The polymer-clay nanocomposites can be simultaneously prepared using the free radicals during γ-irradiation This poly(St-coDVB)-clay nanocomposite could not be used for DMFC membrane because there are no proton-exchange groups and brittle mechanical properties. In order to know the application of the DMFC membrane, DMFC performance for the poly(St-co-NaSS)clay nanocomposite membrane was performed

Experimental

Results and Discussion

Conclusion