Transform Fuel Cell Technology with Our Ultralow Platinum, High-Durability Membrane Electrode Assembly

A method of making a catalyst layer of a membrane electrode assembly ( MEA ) for a polymer electrolyte membrane fuel cell includes the step of preparing a porous buckypaper layer comprising at least one selected from the group consisting of carbon nanofibers and carbon nanotubes . Plati num group metal nanoparticles are deposited in a liquid solution on an outer surface of the buckypaper to create a platinum group metal nanoparticle buckypaper . A proton conducting electrolyte is deposited on the platinum group metal nanoparticles by electrophoretic deposition to create a proton – conducting layer on the an outer surface of the platinum nanoparticles . An additional proton – conducting layer is deposited by contacting the platinum group metal nanoparticle buckypaper with a liquid proton – conducting composition a solvent . The platinum group metal nano particle buckypaper is dried to remove the solvent . A membrane electrode assembly for a polymer electrolyte membrane fuel cell is also disclosed .

We claim : 1. A method of making a catalyst layer of a membrane electrode assembly ( MEA ) for a polymer electrolyte membrane fuel cell , comprising the steps of : preparing a porous buckypaper layer comprising at least one selected from the group consisting of carbon nano fibers and carbon nanotubes ; depositing platinum group metal nanoparticles in a liquid solution on an outer surface of the buckypaper to create a platinum nanoparticle buckypaper ; and , depositing a proton conducting electrolyte on the plati num nanoparticles by electrophoretic deposition to create a proton – conducting layer on the an outer surface of the platinum nanoparticles ; depositing an additional proton – conducting layer by con tacting the platinum nanoparticle buckypaper with a liquid proton – conducting composition in a solvent ; drying the platinum nanoparticle buckypaper to remove the solvent . 2. The method of claim 1 , wherein the step of contacting the platinum nanoparticle buckypaper with a liquid proton conducting composition in a solvent comprises at least one selected from the group consisting of the liquid drop method and the liquid dipping method . 3. The method of claim 1 , wherein the proton – conducting electrolyte comprises at least one selected from the group consisting of Nafion , polyvinylidene fluoride ( PVDF ) / Nafion composite , and Nafion / silica composite . 4. The method of claim 1 , wherein the proton – conducting layer is from 2-10 wt % , based on the total weight of the catalyst layer . 5. The method of claim 1 , wherein the buckypaper has a porosity of from 50 % to 90 % before the deposition of the platinum group metal nanoparticles and the proton – conduct ing layer . 6. The method of claim 1 , wherein the buckypaper layer has a graduated porosity , with the porosity being less on a side of the buckypaper layer to abut a proton exchange membrane of the membrane electrode assembly . 7. The method of claim 6 , wherein the porosity of the buckypaper layer is graduated from a maximum porosity difference of 40 % to a minimum porosity difference of 10 % . 8. The method of claim 1 , wherein the platinum group metal nanoparticles are deposited electrochemically . 9. The method of claim 1 , wherein the platinum group metal nanoparticles have a dimension of from 2 to 10 nm . 10. The method of claim 1 , wherein the platinum group metal nanoparticles are from 30 to 80 % wt % , based on the total weight of the catalyst layer . 11. The method of claim 1 , wherein the buckypaper has less than 1 % binder , based on the total weight of the buckypaper layer . 12. The method of claim 1 , wherein the platinum group metal ( PGM ) nanoparticles comprise at least one selected from the group consisting of platinum , platinum nickel alloy , platinum copper alloy , platinum cobalt alloy , platinum iron alloy , platinum iridium alloy , and platinum palladium alloy . 13. The method of claim 1 , wherein the platinum group metal nanoparticles are core – shell structures including a platinum shell and a core comprising at least one selected from the group consisting of nickel , copper , cobalt , iron , iridium , and palladium . 14. The method of claim 1 , wherein the proton conductivity of the proton – conducting layer is from 0.01-0.2 Siemens / cm . 15. A membrane electrode assembly ( MEA ) for polymer electrolyte membrane fuel cells ( PEMFCs ) , comprising a catalyst layer , the catalyst layer comprising : a porous buckypaper layer comprising at least one selected from the group consisting of carbon nanofibers and carbon nanotubes , the buckypaper having an outer surface ; platinum group metal nanoparticles on the outer surface of the buckypaper , and having outer surfaces ; a proton – conducting electrolyte layer deposited on outer surfaces of the buckypaper and the platinum group metal nanoparticles , the proton conducting layer comprises a first , electrophoretically deposited proton – con ducting layer on the platinum group metal nanoparticles , and a second proton – conducting layer deposited by a liquid contact method on the Pt particles and the buckypaper . 16. The membrane electrode assembly of claim 15 , further comprising a proton exchange membrane . 17. The membrane electrode assembly of claim 16 , further comprising a second catalyst layer , the proton exchange membrane being positioned between the catalyst layers . 18. The membrane electrode assembly of claim 15 , wherein the proton – conducting electrolyte comprises at least one selected from the group consisting of Nation , polyvinylidene fluoride ( PVDF ) / Nafion composite , and Nafion / silica composite . 19. The membrane electrode assembly of claim 15 , wherein the proton – conducting electrolyte layer is from 2-10 wt % , based on the total weight of the catalyst layer . 20. The membrane electrode assembly of claim 15 , wherein the buckypaper has a porosity of from 50 % to 90 % before deposition of the platinum group metal nanoparticles and the proton – conducting layer . 21. The membrane electrode assembly of claim 20 , wherein the buckypaper layer has a graduated porosity , with the porosity being less on a side of the buckypaper layer abutting the proton exchange membrane of the membrane electrode assembly . 22. The membrane electrode assembly of claim 21 , wherein the porosity is graduated from a high of from a maximum porosity difference of 40 % to a minimum porosity difference of 10 % . 23. The membrane electrode assembly of claim 15 , wherein the liquid contact method comprises at least one selected from the group consisting of a liquid dropping method and a liquid dripping method . 24. The membrane electrode assembly of claim 15 , wherein the buckypaper has less than 1 % binder , based on the total weight of the buckypaper layer . 25. The membrane electrode assembly of claim 15 , wherein the platinum group metal ( PGM ) nanoparticles comprise at least one selected from the group consisting of platinum , platinum nickel alloy , platinum copper alloy , platinum cobalt alloy , platinum iron alloy , platinum iridium alloy , and platinum palladium alloy . 26. The membrane electrode assembly of claim 15 , wherein the platinum group metal nanoparticles are core shell structures including a platinum shell and a core comprising at least one selected from the group consisting of nickel , copper , cobalt , iron , iridium , and palladium . 27. The membrane electrode assembly of claim 15 , wherein the platinum group metal nanoparticles have a dimension of from 2-10 nm . 28. The membrane electrode assembly of claim 15 , wherein the platinum group metal nanoparticles are from 30 to 80 % of the catalyst layer , based on the total weight of the catalyst layer . 29. The membrane electrode assembly of claim 15 , wherein the proton conductivity is from 0.01-0.2 Siemens / cm . 30. The membrane electrode assembly of claim 15 , further comprising two electrically conductive and porous gas diffusion layers ( GDL ) connected to the surface of two catalyst layers . 31. The membrane electrode assembly of claim 15 , wherein the catalyst layer is a cathode catalyst layer .