Synthesis of Porous Single-Crystalline Platinum Nanocubes Composed of Nanoparticles.

Single-crystalline platinum nanocubes with porous morphology were synthesized for the first time by using ethylene glycol, HCl, and polyvinylpyrrolidone as the reducing agents of H2PtCl6. The morphology and size distribution of the Pt particles formed were studied with a high-resolution transmission electron microscope and selected-area electron diffraction pattern. By controlling the material concentrations and reaction temperature and period, Pt single crystals about 5 nm in size were formed in the first stage of the reduction process that had {100} facets, which were stacked one on top of the other, forming porous nanocubes 20-80 nm in length. The synthesized Pt nanocubes exhibited enhanced catalytic activity for methanol oxidation.