Universal solvent restructuring induced by colloidal nanoparticles

Abstract

Colloidal nanoparticles, used for applications from catalysis and energy applications to cosmetics, are typically embedded in matrixes or dispersed in solutions. The entire particle surface, which is where reactions are expected to occur, is thus exposed. Here, we show with x-ray pair distribution function analysis that polar and nonpolar solvents universally restructure around nanoparticles. Layers of enhanced order exist with a thickness influenced by the molecule size and up to 2 nanometers beyond the nanoparticle surface. These results show that the enhanced reactivity of solvated nanoparticles includes a contribution from a solvation shell of the size of the particle itself.

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“…This presumably arose from the markedly different microenvironment found in the localized QD-PTE hydration layer. Supporting this notion, a recent report confirms that structural rearrangement of the localized environment around colloidal NPs is a universal phenomenon regardless of what the actual solvent is [16]. We have even found a significant enhancement when working with the large multimeric β-galactosidase enzyme and QDs [17].…”

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