Tetrahedron, Cubo-Octahedronal and Octahedron

The seed-mediated approach represents another effective strategy for the synthesis of tetrahedral Pt nanoparticles using PVP as capping agent and H2 as reductant 

Pt colloids consisting of polyhedra of different shapes (cube, tetrahedron, truncated octahedron) were formed when using H2 as the reductant in basic aqueous solution [77]. The formation of a hydroxylated precursor, and its subsequent reduction, were the two key steps in this process. In the presence of AgN03, the polyol process could also be used to prepare cubo-octahedrons, at a AgN03/Pt(acac)2 molar ratio of approximately 3 25, or octahedrons when the ratio was about 47 100 [9]. 

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