Carbon nanostructures for use as catalyst supports in hydrogen fuel cells are produced by mixing a carbon material with at least one transition metal such as iron and cobalt, subjecting the mixture thus produced to mechanical grinding, e.g. ball milling in a hydrogen atmosphere for a time sufficient for hydrogen to be absorbed into the mixture, and heating the mixture in an inert atmosphere at a temperature sufficient to crystallize at least one of the carbon material and carbide nanocrystals.