A new technique to deposit nanoparticles synthesized in reverse micellar microemulsions onto support material without agglomeration is named thermal destabilization of microemulsion. The multifaceted Pt crystals, mostly truncated octahedra, were produced inside reverse micelles with an average size of 2.5 nm and a narrow size distribution. After deposition, the Pt crystals were found to be well dispersed on the support with an average size of 2.5 nm. After testing with hydrogenation of a-methyl styrene, the produced Pt-catalyst showed higher activity (6 times higher) and stability than commercial ones. The advantages of this synthesis route of nanoparticles include simple operation, and the ease of controlling the size and shape of nanoparticles without using capping agents.