Novel nanocomposite membranes based on cross-linked eco-friendly polymers doped with sulfated titania nanotubes for direct methanol fuel cell application

Mh Gouda,Abdelaziz H Konsowa,Noha A Elessawy,Hassan A Farag,Tamer M Tamer,Mohamed S Mohy Eldin

doi:10.1177/1847980420964368

Abstract

Developing low cost and highly active fuel cell is one of the high-priority research directions for fuel cell commercialization, whereas durable electrodes and electrolyte membranes are keys for its optimization. Herein, a novel nanocomposite electrolyte membranes for direct methanol fuel cell were prepared from eco-friendly polymer blend composed of poly(vinyl alcohol) (PVA) and iota carrageenan (IC). Sulfated titania (SO4TiO2) nanotubes are synthesized by impregnation–calcination method and incorporated as doping agents into the polymer matrix with different percentage ranged between 1 wt% and .5 wt%. The PVA/IC/SO4TiO2 nanocomposite membranes exhibited reduction in water and methanol uptake compared to that of undoped membrane, while the thermal properties and oxidative stability increased as the doping agent content increased. Methanol permeability of PVA/IC/[Formula: see text]-TiO2-7.5 membrane was 0.62 × 10−7 cm2 s−1, which is 43 times lower than Nafion 117 (26.9 × 10−7 cm2 s−1). Furthermore, it was noticed that the ion exchange capacity and mechanical properties of the nanocomposite membranes are higher than that of Nafion 117.

Highlights

Fuel cell technologies are new, attracting more attention as energy conversion tools targeting elimination of the fossil fuel pollution,[1,2] whereas fuel cell gives electricity with efficiency above 50% and can provide high power density for a long time at low operating temperatures.[3]
In Direct methanol fuel cells (DMFCs), membrane acts as a separator between cathode and anode compartments in addition to allowing hydrogen ions (Hþ) transfer from anode to cathode effectively and hindering the methanol crossover effect.[3,5]
There are two essential types of membranes according to the type of transferred ion charge classification, such as cation-exchange membranes (CEMs) for cation transfer and anion-exchange membranes (AEMs) for anions transfer.[3,6]

Summary

Introduction

Fuel cell technologies are new, attracting more attention as energy conversion tools targeting elimination of the fossil fuel pollution,[1,2] whereas fuel cell gives electricity with efficiency above 50% and can provide high power density for a long time at low operating temperatures.[3] Direct methanol fuel cells (DMFCs) are polymer electrolyte fuel cells having some advantages, such as methanol, as fuel has high hydrogen to carbon ratio (4:1), the simple design of the DMFC, and its eco-friendly impact.[4]. Many researchers are concerned about developing cost-effective and eco-friendly membranes based on green synthesis.[7]

Methods

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Discussion

Conclusion