Sulfonated conducting polymer-grafted carbon material for fuel cell applications
View Patent ↗A composition comprising particulate carbonaceous material and a sulfonated conducting polymer containing hetero atoms. The composition can further comprise a metal. Devices comprising the composition can be constructed including supported electrocatalysts, membrane electrode assemblies, and fuel cells. A method for preparing the composition comprises oxidatively polymerizing with ozone a monomer of a conducting polymer containing hetero atoms in the presence of a carbonaceous material and sulfonating the polymer or the monomer. The method grafts the sulfonated conducting polymer to the carbonaceous material. The method can further comprise metallizing the polymer-grafted carbonaceous material.
1. A method for preparing a carbon composition with enhanced electronic and protonic conductivity comprising
oxidatively polymerizing with an oxidizing agent comprising ozone a monomer of a conducting polymer containing hetero atoms with particulate carbonaceous material to form a conducting polymer-grafted carbonaceous material, wherein either the monomer is sulfonated or the polymer is subsequently sulfonated, to thereby produce a sulfonated conducting polymer-grafted carbonaceous material; and metallizing the conducting polymer-grafted carbonaceous material.
2. The method of claim 1 , wherein the carbonaceous material is carbon black, graphite, nanocarbons, fullerenes, fullerenic material, finely divided carbon, or mixtures thereof.
3. The method of claim 1 , wherein the carbonaceous material is carbon black.
4. The method of claim 1 , wherein the monomer of a conducting polymer is an amino aryl or a nitrogen heterocycle.
5. The method of claim 1 , wherein the oxidatively polymerizing comprises adding ozone to a mixture of the carbonaceous material and the monomer of the conducting polymer.
6. The method of claim 5 , wherein the mixture of the carbonaceous material and the monomer of the conducting polymer further comprises an acid solvent to form a slightly acidic environment.
7. The method of claim 6 , wherein the slightly acidic environment is a pH of about less than 7.
8. The method of claim 6 , wherein the slightly acidic environment is a pH of about 3 to about 4.
9. The method of claim 1 , wherein the conducting polymer is polyaniline, polypyrrole, polyfuran, polythiophene, poly(p-phenylene-oxide), poly(p-phenylene-sulfide), substituted conducting polymers, or a mixture thereof.
10. The method of claim 1 , wherein the polymer is directly sulfonated after oxidatively polymerizing the monomer with the carbonaceous material.
11. The method of claim 1 , wherein the monomer is a sulfonated monomer of the conducting polymer.
12. The method claim 10 , wherein the direct sulfonation is by addition of a sulfonating agent.
13. The method claim 12 , wherein the sulfonating agent is chlorosulfonic acid.
14. The method claim 12 , wherein the sulfonating agent is acetylsulfonic acid.
15. The method of claim 1 , wherein the metallizing comprises adding a metal-containing material to the conducting polymer-grafted carbonaceous material.
16. The method of claim 15 , wherein the metallizing further comprises adding a reducing agent.
17. The method of claim 1 , wherein the metallizing is plantinizing.
18. The method of claim 16 , wherein the reducing agent is formaldehyde, sodium borohydride, hydrogen, hydrazine, hydroxyl amine, or a mixture of reducing agents.
19. The method of claim 15 , wherein the metal-containing material is chloroplatinic acid, platinum nitrate, platinum halide, platinum cyanide, platinum sulfide, organoplatinum salt, or a mixture thereof.