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The article discusses the development of a new strategy, which can be employed for the rational synthesis of different heterostructured nanoparticles. The morphology control mechanism for the nanoparticles is shown to be extremely beneficial in making them fit for catalytic and functional applications.

The monodisperse Pt nanocubes are synthesized by the reduction of platinum acetylacetonate (Pt[(acac).sub.2]) in the presence of oleic acid and oleylamine and a trace amount of Fe[(CO).sub.5]. The nanocubes of a carbon paper have indicated an increased catalysis toward oxygen reduction and their specific activity is higher than that from the commercial Pt catalyst.

We report the design and synthesis of multimetallic Au/Pt-bimetallic nanoparticles as a highly durable electrocatalyst for the oxygen reduction reaction (ORR) in proton exchange membrane fuel cells. This system was first studied on well-defined Pt and FePt thin films deposited on a Au(111) surface, which has guided the development of novel synthetic routes toward shape-controlled Au nanoparticles coated with a Pt-bimetallic alloy. It has been demonstrated that these multimetallic Au/FePt(3) nanoparticles possess both the high catalytic activity of Pt-bimetallic alloys and the superior durability of the tailored morphology and composition profile, with mass-activity enhancement of more than 1 order of magnitude over Pt catalysts. The reported synergy between well-defined surfaces and nanoparticle synthesis offers a persuasive approach toward advanced functional nanomaterials.

Monodisperse dumbbell-like Pt-Fe(3)O(4) nanoparticles are synthesized by epitaxial growth of Fe onto Pt nanoparticles followed by Fe oxidation. The nanoparticle size in the structure is tunable from 2 to 8 nm for Pt and 6 to 20 nm for Fe(3)O(4). Pt nanoparticles in the Pt-Fe(3)O(4) structure show a 20-fold increase in mass activity toward oxygen reduction reaction compared with the single component Pt nanoparticles and the commercial 3 nm Pt particles. The work proves that it is possible to maximize catalytic activity of the Pt nanoparticle catalyst through the control not only of Pt size and shape but also of its interaction with Fe(3)O(4) nanoparticles.