Advanced Materials

Formation of an Isolated Spherical Three-Dimensional Nanoparticle Assembly as Stable Submicrometer-Sized Units by Using an Inorganic Wrapping Technique


  • This work was partly supported by the Nippon Sheet Glass Foundation for Material Science and Engineering. Financial support came from the Grants-in-Aid for Encouragement of Young Scientists (to TY, 12740383) and for COE Research (08CE2005) as well as the JSPS Research Fellowships for Young Scientists (to HM). Supporting information is available from the authors upon request.


A novel inorganic wrapping technique has been used to create stable, three-dimensional spherical assemblies of gold nanoparticles. Uniform, crack-free TiO2 layers of 5 nm thickness could be wrapped around the nanoparticle assemblies using a sol–gel technique. Upon addition of a suitable surfactant these particles are stable in organic media (see Figure: with (right) and without (left) suitable surfactant).