Electrostatic Aggregation and Formation of Core−Shell Suprastructures in Binary Mixtures of Charged Metal Nanoparticles

Abstract

Electrostatic aggregation of oppositely charged silver and gold nanoparticles leads to the formation of core-shell clusters in which the shell is formed by the nanoparticles, which are in excess. Arguments based on Debye screening of interactions between like-charged particles help explain why these clusters are stable despite possessing net electric charge. The core-shell aggregates exhibit unusual optical properties with the resonance absorption of the shell particles enhanced by the particles in the core and that of the core suppressed by the shell. Experimental UV-vis absorption spectra are faithfully reproduced by Mie theory. The modeling allows for estimation of the numbers of particles forming the shell and of the shell's effective thickness. These theoretical predictions are substantiated by experiments using nanoparticles covered with different combinations of charged groups and performed at different values of pH.

Nanoparticle Clusters: Assembly and Control Over Internal Order, Current Capabilities, and Future Potential

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Imidazolium ionic liquid induced one-step synthesis of 𝜶-Fe2O3 nanorods and nanorod assemblies for lithium-ion battery

“…[6][7][8] Various morphologies including nanoplates, nanospindles, nanocubics, and nanorods have been reported. 9,10 Self-assembly can be induced by non-covalent interactions such as van der Waals force, 11 electrostatic force, 12 dipole-dipole interaction, 13 and hydrogen-bonding. 14 Typically, the self-assembly procedure is associated with multiple steps.…”

Exploring New Synthetic Strategies for the Production of Advanced Complex Inorganic Nanocrystals

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