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Air-Stable, Nanostructured Electronic and Plasmonic Materials from Solution-Processable, Silver Nanocrystal Building Blocks

Research output: Contribution to journalArticleScientificpeer-review

Details

Original languageEnglish
Pages (from-to)2746-2754
Number of pages9
JournalACS Nano
Volume8
Issue number3
DOIs
Publication statusPublished - Mar 2014
Externally publishedYes
Publication typeA1 Journal article-refereed

Abstract

Herein we describe a room-temperature, chemical process to transform silver nanocrystal solids, deposited from colloidal solutions, into highly conductive, corrosion-resistant, optical and electronic materials with nanometer-scale architectures. After assembling the nanocrystal solids, we treated them with a set of simple, compact, organic and inorganic reagents: ammonium thiocyanate, ammonium chloride, potassium hydrogen sulfide, and ethanedithiol. We find that each reagent induces unique changes in the structure and composition of the resulting solid, giving rise to films that vary from insulating to, in the case of thiocyanate, conducting with a remarkably low resistivity of 8.8 x 10(-6) Omega . cm, only 6 times that of bulk silver. We show that thiocyanate mediates the spontaneous sintering of nanocrystals into structures with a roughness of less than 1/10th of the wavelength of visible light. We demonstrate that these solution-processed, low-resistivity, optically smooth films can be patterned, using imprint lithography, into conductive electrodes and plasmonic mesostructures with programmable resonances. We observe that thiocyanate-treated solids exhibit significantly retarded atmospheric corrosion, a feature that dramatically increases the feasibility of employing silver for electrical and plasmonic applications.

Keywords

  • silver nanoparticles, ligand exchange, ammonium thiocyanate, conductivity, dielectric function, metamaterials, nanoimprinting, soft lithography, printing, electrodes, COLLOIDAL NANOCRYSTALS, MILD TEMPERATURES, CHARGE-TRANSPORT, ROOM-TEMPERATURE, NANOPARTICLES, THIOCYANATE, SOLIDS, FILMS, CONDUCTIVITY, SPECTROSCOPY