Influence of iron on structure and catalyst activity of nitrogen-functionalized graphene nanoflakes

Toward Pt-Free Anion-Exchange Membrane Fuel Cells: Fe–Sn Carbon Nitride–Graphene Core–Shell Electrocatalysts for the Oxygen Reduction Reaction

“…Graphene nanoplatelet cores are adopted with the aim to exploit (a) their negligible microporosity, to facilitate the mass transport of reactants (e.g., oxygen) and products (e.g., water) in the cathodic electrocatalytic layer of the AEMFC, and (b) their high electrical conductivity, to minimize the ohmic losses associated with the electron transport from the active sites to the external circuit. − The proposed graphene-based ECs are significantly different than those described in literature. In fact, the latter typically include oxide or nitride nanoparticles bearing the active sites to promote the ORR in an alkaline environment. , Furthermore, the ECs described in literature do not comprise a CN matrix shell . , Differently, in the proposed core–shell Pt-free ECs, the CN shell (i) is templated on the GNP core and (ii) coordinates the ORR active sites based on iron and tin. Thus, in the proposed core–shell Pt-free ECs, the active sites are not found on the surface of inorganic nanoparticles, forming a distinct component within the system.…”

“…41,42 Furthermore, the ECs described in literature do not comprise a CN matrix shell. 43,44 Differently, in the proposed core−shell Pt-f ree ECs, the CN shell (i) is templated on the GNP core and (ii) coordinates the ORR active sites based on iron and tin. Thus, in the proposed core−shell Pt-f ree ECs, the active sites are not found on the surface of inorganic nanoparticles, forming a distinct component within the system.…”