Hierarchically Organized Nanoparticle Mesostructure Arrays Formed through Hydrothermal Self-Assembly

We report a new self-assembly pathway that leads to supported and hierarchically organized gold nanoparticle mesostructure arrays on solid substrates such as glass slide, thermal oxide, photopolymer film, and mica. Using the nanoparticle micelle as a building block, hierarchical gold nanoparticle mesostructure arrays were prepared by a hydrothermal nucleation and growth process through self-assembly of nanoparticle micelles and organosilicates under basic conditions. Depending on the substrates used, the shape, order, and orientation of the gold nanoparticle mesostructure during nucleation and growth exhibit distinct features. Transmission electron microscopy and X-ray diffraction results revealed that gold nanoparticles were organized as a face-centered cubic mesostructure with precisely controlled interparticle spacing. Optical characterization using UV-vis spectroscopy shows a characteristic surface plasmon resonance band resulted from the ordered nanoparticle arrays. This method provides new means for colloidal self-assembly and for the fabrication of platforms for surface enhanced Raman scatteringbased sensors and electric and optical nanodevices with enhanced thermal, chemical, and mechanical robustness.