Pt nanoparticles supported on mesoporous carbon nanocomposites incorporated with Ni or Co nanoparticles for fuel cells

Abstract

We report the preparation and characterization of mesoporous carbon nanocomposites with Ni and Co nanoparticles incorporated into the pore walls, which are synthesized via template strategy by sucrose-impregnation and benzene chemical vapor deposition (CVD) routes separately. Pt nanoparticles supported on the nanocomposites for oxygen reduction reaction (ORR) and methanol oxidation reaction (MOR) in fuel cells are fabricated via hydrogen reduction method. It is found that the introduction of metal nanoparticles into the pore walls of carbon materials via both synthesis routes had negligible change in pore structure. Highly dispersed Pt nanoparticles supported on nanocomposites synthesized by sucrose-impregnation method shows better catalytic activities for both ORR and MOR than that on those by CVD method and greatly improve the limiting current densities for ORR. The promotional effect of Ni on the catalytic activity of Pt catalysts for both ORR and MOR is evidenced in nanocomposites obtained with sucrose-impregnation method, but not with CVD method. Interesting results revealed that Ni performed as a better promoter in MOR while Co is a better promoter in ORR. Our investigation not only provides further insight on the roles of Ni and Co in ORR and MOR, but also can assist the design and synthesis of the new nanostructured electrocatalyst supports.