Reduced Graphene Oxide-Nanosheet/Polybenzimidazole Composite Membranes for High Temperature Proton Exchange Membrane Fuel Cell Applications

Background/Relevance

• Increasing the operating temperature of proton exchange membrane fuel cells (PEMFC) will increase efficiency and enable the development of less expensive materials

• Nanomaterial filler in the PEM introduces additional proton conductivity and reduces degradation caused by the phosphoric acid (PA) proton transport medium, increasing the durability and performance of the PEMFC

Innovation

• Boosted proton conductivity of reduced graphene oxide(RGO)-based composite nanomaterial offers superior acid resistance, proton conduction, and mechanical reinforcement

Approach

• Hydrothermally synthesize proton conductive RGO nanomaterial composite, including additional functionalization for increased proton conductivity and nano-blending
• Drop cast PBI PEMs containing a range of concentrations of nanomaterial filler and observe their PA uptake
• Characterize the mechanical properties and proton conductivities of PEM’s over a range of nanomaterial content, PA content and temperatures
• Create membrane electrode assembly (MEA) using new PEM’s to test PEMFC performance.

Key Results

• RGO composite and subsequent protonation to introduce proton conductivity successfully performed
• Strong nano-blending between PBI and RGO composite confirmed
• New PEMs with different filler concentrations formed, further optimization ongoing

Conclusions

• A proton-rich RGO composite nanomaterial with great PEM filler potential can be hydrothermally synthesized at a low cost

• The nano-blending between PBI and RGO can be optimized to effectively mass produce advanced PEMs

Future Work

• Synthesize composite nanomaterial using functionalized RGO

• Investigate the filler’s ability to increase the mechanical properties of the membrane and decrease acid leeching

• Quantify the proton conductivity and test MEA performance at different temperatures and PA loadings

• Assess the potential to form RGO composites with advanced proton conducting materials