Shape Control of Catalysts in Colloidal Synthesis

Oleic acid and oleylamine are used as the capping agents to control the growth of metal and metal alloy nanoparticles [16]. Cube, octahedral, prism, tripod, octapod, rod, and various other shapes have been obtained by using these two surfactants [16c]. Pt cubes, tripods, and multipods were made by using alternative surfactants, such as ada-mantinecarboxylic acid (ACA) and hexadecylamine (HDA) [17]. 

FIGURE 2.2 (a-c) TEM and (d-f) HR-TEM micrographs of octahedral Pt-Ni alloy nanocrystals (a,d) PtjNi, (h,e) PtNi, and (c,f) PtNi. Reprinted with permission from Ref [19]. American Chemical Society. 

---