Green and Low-Cost Membrane Electrode Assembly for Proton Exchange Membrane Fuel Cells: Effect of Double-Layer Electrodes and Gas Diffusion Layer

M H Gouda,M Elsayed Youssef,Noha A Elessawy,Andrew N Aziz,Mohamed Elnouby,D M F Santos

doi:10.3389/fmats.2019.00337

Abstract

The success of fuel cells depends on the design structure meanwhile catalysts electrodes and membrane allowing easy access of oxygen and protons. Using non-precious catalyst electrodes based on recyclable carbon nanostructures is most important to produce clean energy and increase the ability to commercialize the fuel cells. Herein, reduced graphene oxide (rGO) and graphene/magnetic iron oxide nanocomposite (rGO/MIO) are successfully synthesized as anode and cathode respectively from polyethylene terephthalate (PET) waste bottles using easy steps in order to simplify the method and reducing the production cost. While, the membrane is prepared from low cost and eco-friendly ternary polymers blend which are polyvinyl alcohol (PVA), polyethylene oxide (PEO) and polyvinyl pyrrolidone (PVP) then doped with sulfonated graphene oxide. The prepared electrodes have characteristic high porosity and their electrocatalytic performances are evaluated using three-electrode cell electrochemical studies as cyclic voltammetry and linear scan voltammetry combined with rotating disk electrode. A new assembly of the membrane between two non-precious catalyst electrodes as a single polymer electrolyte membrane fuel cell (PEMFC) was developed using a catalyst-coated membrane technique. The membrane electrode assembly (MEA) design parameters which affect its performance in hydrogen fuel cells as number of used catalyst layers (CL) or using gas diffusion layer (GDL) were evaluated in a single cell set-up with H2/O2 operation and the results revealed that the performance MEA was enhanced with using GDL more than that of MEA without GDL by 66% at a current density of 0.8 A cm−2 while the performance with double CL was better than that of the conventional single CL by 30 % at a current density of 0.98 mA cm−2.

Highlights

As a result of the rapid urbanization since the beginning of the last century, the global growth of fossil fuel energy consumption has increased, leading to an increase in environmental pollution rate
It was noticed that the surface area and the pore size of reduced graphene oxide (rGO)/MIO nanocomposite is higher than that of rGO indicating that, the introducing of iron oxide nanoparticles avoids the aggregation and restacking problems which led to an obvious increase in BET surface area and pore size and that is a valuable characteristic for electrocatalytic applications
For rGO/MIO sample, a slight shift for (002) plane was due to introducing of Fe3O4 nanoparticles between the rGO nanosheets increasing the interlayer spacing and that is beneficial to promote charge transfer in electrodes materials

Summary

Introduction

As a result of the rapid urbanization since the beginning of the last century, the global growth of fossil fuel energy consumption has increased, leading to an increase in environmental pollution rate. High-performance nonprecious metal catalysts (NPMCs) simultaneously active for the ORR at the cathode and the hydrogen oxidation reaction (HOR) at the anode are desperately needed to replace these precious metals and to solve the drawbacks (Gupta et al, 2016). Under these circumstances, transition metal oxides (Gao et al, 2017; Lai et al, 2017), hybrid inorganic nanocarbon materials (Su et al, 2014; Ye et al, 2017) and carbon-doped metal-free heteroatom nanomaterials (Dumont et al, 2019) were used to substitute platinum for constructing highly efficient nonprecious metal catalysts. The promoted activity of doped carbon materials may be attributed to the electron-donating or electron-accepting behavior between adjacent carbon atoms and the heteroatoms, which modify the charge allocation in the carbon plane (Shen et al, 2014)

Methods

Results

Conclusion