Non-precious metal catalysts prepared from precursor comprising cyanamide
View Patent ↗Catalyst comprising graphitic carbon and methods of making thereof; said graphitic carbon comprising a metal species, a nitrogen-containing species and a sulfur containing species. A catalyst for oxygen reduction reaction for an alkaline fuel cell was prepared by heating a mixture of cyanamide, carbon black, and a salt selected from an iron sulfate salt and an iron acetate salt at a temperature of from about 700° C. to about 1100° C. under an inert atmosphere. Afterward, the mixture was treated with sulfuric acid at elevated temperature to remove acid soluble components, and the resultant mixture was heated again under an inert atmosphere at the same temperature as the first heat treatment step.
1. A catalyst prepared by a process comprising:
heating a mixture of cyanamide, carbon black, and an iron sulfate salt at a temperature of from about 1050° C. to about 1100° C. under an inert atmosphere, and
removing acid-soluble components from the mixture.
2. The catalyst of claim 1 , wherein said catalyst comprises a graphitic carbon.
3. The catalyst of claim 2 , wherein said catalyst comprises a pyridinic nitrogen and a pyrrole nitrogen.
4. A membrane electrode assembly prepared by a process comprising:
preparing a catalyst by heating a mixture of cyanamide, carbon black, and an iron sulfate salt at a temperature of from about 1050° C. to about 1100° C. under an inert atmosphere and thereafter removing acid-soluble components from the mixture and thereafter heating the mixture from about 1050° C. to about 1100° C. under an inert atmosphere to form the catalyst,
mixing the catalyst with water and with an ionomer suspension to form a catalyst composition;
applying the catalyst composition onto a first side of a membrane;
applying the catalyst composition onto a first side of a gas diffusion layer;
forming a membrane electrode assembly by placing the first side of the membrane in direct contact with the first side of the gas diffusion layer; and
applying heat and pressure to the membrane electrode assembly.
5. A method of forming a catalyst comprising:
a) mixing a cyanamide precursor material, a metal-sulfate precursor material and carbon black to form a graphitic C 3 N 4 compound;
b) heating the mixture at a temperature of from about 1050° C. to about 1100° C. in an inert atmosphere; and,
c) removing acid-soluble components from the mixture.