The interest of nanoparticle-based aerogels—3-dimensional (3D) nanoparticle assemblies macroscopic sizes—in photocatalysis is mainly their versatility for tailoring properties.

Two-dimensional assemblies of Au-Pt bimetallic nanoparticles are generated in situ on polyethyleneimmine (PEI) silane functionalized silicon and indium tin oxide (ITO) coated glass surfaces. Atomic force microscopy (AFM), UV-Visible spectroscopy, and electrochemical measurements reveal the formation of core-shell structure with Au as core and Pt as shell. The core-shell structure is further sup...

In the work reported in this paper, we demonstrate that Ag–Keggin ion colloidal particles are excellent templates for the synthesis of organized assemblies of silver nanoparticles, wherein the Keggin ion host plays the role of a UV-switchable reducing agent. More specifically, we investigate the formation of aqueous colloidal particles of Ag ions complexed with phosphotungstate (PW12O40) 32 Keg...

Magnetostatic (dipolar) interactions between nanoparticles promise to open new ways to design nanocrystalline magnetic materials and devices if the collective magnetic properties can be controlled at the nanoparticle level. Magnetic dipolar interactions are sufficiently strong to sustain magnetic order at ambient temperature in assemblies of closely-spaced nanoparticles with magnetic moments of...

A gold nanoparticle-based competitive colorimetric assay can detect mismatched DNAs using MutS, a mismatch binding protein, and determine their relative binding affinities for this protein by a simple color change and the melting temperature of DNA-functionalized nanoparticle assemblies.

We have achieved highly localized control of pattern formation in two-dimensional nanoparticle assemblies by direct modification of solvent dewetting dynamics. A striking dependence of nanoparticle organization on the size of atomic force microscope-generated surface heterogeneities is observed and reproduced in numerical simulations. Nanoscale features induce a rupture of the solvent-nanoparti...

We demonstrate the ability of stimulated emission depletion (STED) microscopy, a far-field fluorescence imaging technique with diffraction-unlimited resolution, to reveal the spatial order of fluorescent nanoparticles. Unlike its confocal counterpart, here STED microscopy resolves the arrangements of densely packed 40 nm beads, supramolecular aggregates in a cell membrane, and colloidal nanopar...

Enzymatic ligation of discrete nanoparticle-DNA conjugates creates nanoparticle dimer and trimer structures in which the nanoparticles are linked by single-stranded DNA, rather than by double-stranded DNA as in previous experiments. Ligation was verified by agarose gel and small-angle X-ray scattering. This capability was utilized in two ways: first, to create a new class of multiparticle build...