Observation of exchanging role of gold and silver nanoparticles in bimetallic thin film upon annealing above the glass transition temperatureShow others and affiliations
2017 (English)In: Materials Research Express, E-ISSN 2053-1591, Vol. 4, no 8, article id 086409Article in journal (Refereed) Published
Abstract [en]
The exchange role of gold (Au) and silver (Ag) in bimetallic films co-evaporated onto soda-lime glass substrates with Au-Ag volume ratios of 1:2, 1:1 and 2:1 have been demonstrated. Annealing of the films above the glass transition temperature in air led to non-alloying nature of the films, silver neutrals (Ag-0) and gold nanoparticles (AuNPs) on the surface, along with silver nanoparticles (AgNPs) inside the glass matrix. Moreover, the size distribution and interparticle spacing of the AuNPs on the surface were governed by the Ag content in the deposited film. In contrast, the content of Au in the film played an opposite role leading to the migration of Ag ions (i.e. Ag-0 being transformed to Ag ions after annealing in oxygen ambient) to form AgNPs inside the glass matrix. The higher the Au content in the film is, the more likely Ag-0 to stay on the surface and impacts on the size distribution of AuNPs and consequently on the refractive index sensitivity measurements. Experimental realisation of this fact was reflected from the best performance for localized surface plasmon resonance (LSPR) sensitivity test achieved with Au-Ag ratio of 1:2. The Au/Ag/glass bimetallic dynamic results of this study can be pertinent to sensor applications integrated with optical devices.
Place, publisher, year, edition, pages
IOP PUBLISHING LTD , 2017. Vol. 4, no 8, article id 086409
Keywords [en]
gold-silver bimetallic nanoparticles, film, nanoparticle surface, nanocomposites, annealing, refractive index sensitivity
National Category
Materials Engineering
Identifiers
URN: urn:nbn:se:kth:diva-214343DOI: 10.1088/2053-1591/aa84e6ISI: 000407979700003Scopus ID: 2-s2.0-85029174380OAI: oai:DiVA.org:kth-214343DiVA, id: diva2:1140466
Note
QC 20170912
2017-09-122017-09-122022-06-27Bibliographically approved