Characterization of the interface between metal and tris (8-hydroxyquinoline) aluminum using surface-enhanced Raman scattering with glass cap encapsulation

• Published in: Chemical physics letters 2010-08, Vol.496 (1), p.91-94
• Main Authors: Muraki, Naoki, Yoshikawa, Masanobu
• Format: Article
• Language: English
• ISSN: 0009-2614; 1873-4448
• DOI: 10.1016/j.cplett.2010.07.011

[Display omitted] . ► Glass cap encapsulation in dry nitrogen enables reproducible and stable SERS measurements. ► The SERS signal of Alq 3 was stable for at least 2 months. ► Vapor deposition of Ag onto Alq 3 films shows new vibrational modes assigned to radical anion of Alq 3. ► The technique is applied to investigate the interface between the deposited metal and the Alq 3. Encapsulation with a glass cover in a dry nitrogen atmosphere after metal deposition is found to be effective for obtaining reproducible and stable surface-enhanced Raman spectra of tris (8-hydroxyquinoline) aluminum (Alq 3). Vapor deposition of Au onto Alq 3 films shows enhanced Raman bands of neutral Alq 3, whereas deposition of Ag results in the appearance of new vibrational modes assigned to radical anions of Alq 3. The Raman intensity of the encapsulated sample was stable for 2 months. The effect of the insertion of a sub-nm layer of LiF, Mg, or Al between the deposited Au and the Alq 3 layer is also investigated.