Coating procedure for chemical and morphological functionalization of multilayer-graphene foams

A new strategy for designing the morphology and the chemical/physical properties of carbon structures is developed by functionalization of porous carbon templates. In a thermal decomposition procedure self-prepared multilayer-graphene foams (GF) are coated with a nitrogen-containing carbon layer (NCL) which has a porous structure. The use of a nitrogen rich ionic liquid as precursor generates a NCL with a very high nitrogen level of 35.3 wt%. To the best of our knowledge, this is the first synthesis of a hierarchical structured N-GF with such a high nitrogen amount. Structural studies on the NCL confirm C5N and C3N4 species. Compared to uncoated GF it could be demonstrated that the functionalized porous carbon template (N-GF) has an increased electronic conductivity and electrochemical stability. Electrochemical characterizations of polymer electrolyte membrane fuel cells (PEMFC) prepared with Pt catalysts supported on N-GF show an increased performance which is attributed to improved mass transport properties and higher electronic conductivity of the porous composite material. Morphological, structural, chemical, and electrochemical characterizations were performed.

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