Aluminum Film-Over-Nanosphere Substrates for Deep-UV Surface-Enhanced Resonance Raman Spectroscopy

Bhavya Sharma; M Fernanda Cardinal; Michael B Ross; Alyssa B Zrimsek; Sergei V Bykov; David Punihaole; Sanford A Asher; George C Schatz; Richard P Van Duyne

doi:10.1021/acs.nanolett.6b04296

Aluminum Film-Over-Nanosphere Substrates for Deep-UV Surface-Enhanced Resonance Raman Spectroscopy

Nano Lett. 2016 Dec 14;16(12):7968-7973. doi: 10.1021/acs.nanolett.6b04296. Epub 2016 Nov 16.

Authors

Bhavya Sharma^{1

2}, M Fernanda Cardinal¹, Michael B Ross¹, Alyssa B Zrimsek¹, Sergei V Bykov³, David Punihaole³, Sanford A Asher³, George C Schatz¹, Richard P Van Duyne¹

Affiliations

¹ Department of Chemistry, Northwestern University , 2145 Sheridan Road, Evanston, Illinois 60208, United States.
² Department of Chemistry, University of Tennessee , 1420 Circle Drive, Knoxville, Tennessee 37996, United States.
³ Department of Chemistry, University of Pittsburgh , 219 Parkman Avenue, Pittsburgh, Pennsylvania 15260, United States.

PMID: 27960451
DOI: 10.1021/acs.nanolett.6b04296

Abstract

We report here the first fabrication of aluminum film-over nanosphere (AlFON) substrates for UV surface-enhanced resonance Raman scattering (UVSERRS) at the deepest UV wavelength used to date (λ_ex = 229 nm). We characterize the AlFONs fabricated with two different support microsphere sizes using localized surface plasmon resonance spectroscopy, electron microscopy, SERRS of adenine, tris(bipyridine)ruthenium(II), and trans-1,2-bis(4-pyridyl)-ethylene, SERS of 6-mercapto-1-hexanol (as a nonresonant molecule), and dielectric function analysis. We find that AlFONs fabricated with the 210 nm microspheres generate an enhancement factor of approximately 10^4-5, which combined with resonance enhancement of the adsorbates provides enhancement factors greater than 10⁶. These experimental results are supported by theoretical analysis of the dielectric function. Hence our results demonstrate the advantages of using AlFON substrates for deep UVSERRS enhancement and contribute to broadening the SERS application range with tunable and affordable substrates.

Keywords: UV resonance Raman spectroscopy (UVRRS); aluminum plasmonics; film-overnanosphere substrates; surface-enhanced Raman spectroscopy (SERS).

Publication types

Research Support, Non-U.S. Gov't
Research Support, U.S. Gov't, Non-P.H.S.