초록 |
Limited synthetic scales of liquid-phase synthetic methods preclude large-scale production of supported Pt-alloy nanoparticles with desirable catalytic performance. Herein, we investigated on a uniform decomposition of bimetallic compounds on carbon supports, obtaining uniformly sized Pt-alloy nanoparticles. Two different kinds of metal complexes with opposite charges are mixed together to form bimetallic compounds formulated as [M(bpy)3]2+[PtCl6]2-, M = Fe, Co, Ni, bpy = 2,2’-bipyridine). The bimetallic compound grains with sizes of several hundreds of nanometer are then attached on carbon supports such as graphene oxide. Upon thermal annealing under argon atmosphere, the bimetallic compound decomposes and is well spread on the entire surface of carbon. Thereafter, MPt alloy nanoparticles grow in a uniform size range. We observed a representative HAADF-STEM image of an L10-FePt nanoparticle, showing a clear atomic arrangement of intermetallic structure. We generalized the synthesis by obtaining FePt, CoPt and NiPt nanoparticles on reduced graphene oxide support, and by using other kinds of cationic metal complexes and carbon supports for the synthesis of FePt nanoparticles. |