Two-dimensional combinatorial investigation of raman and fluorescence enhancement in silver and gold sandwich substrates
2009 (English)In: Journal of Physical Chemistry C, ISSN 1932-7447, Vol. 113, no 22, 9588-9594 p.Article in journal (Refereed) Published
We present a two-dimensional combinatorial investigation of resonant Raman and fluorescence enhancement in silver and gold sandwich structures. Gold and silver, separated by a thin alumina spacer layer, were deposited in two orthogonal gradients, with a thickness from a few hundred to a few nanometers, covering the range from island films through percolation to continuous films. Resonant Raman spectra of Rhodamine 6G adsorbed on the substrate surface were recorded in a 13 × 13 matrix using an automated scanning stage. The most Raman-active substrates were composed of silver (8 nm)-on-alumina (7 nm)-on-gold (5 nm). They consist of both gold and silver discontinuous nanoparticle films separated by alumina, forming a labyrinthine network structure. Gold-on-alumina-on-silver substrates also displayed increased activity compared with that of goldon-alumina substrates. Maximum fluorescence intensity was observed on silver films nominally 35 nm thick covered by 8 nm of alumina. The efficacy of the combinatorial method to correlate multiple aspects of the measurements and reduce uncertainties is demonstrated.
Place, publisher, year, edition, pages
2009. Vol. 113, no 22, 9588-9594 p.
IdentifiersURN: urn:nbn:se:liu:diva-21327DOI: 10.1021/jp900436aOAI: oai:DiVA.org:liu-21327DiVA: diva2:241066