Journal of Fluorescence

, Volume 16, Issue 2, pp 215–219 | Cite as

A Molecular Thermometer Based on the Delayed Fluorescence of C70 Dispersed in a Polystyrene Film

Original Article

A new optical molecular thermometer, based on the thermally activated delayed fluorescence of C70 dispersed in a polystyrene film, was developed. In the presence of oxygen, the fluorescence intensity of the C70 film is essentially temperature independent in a wide range. In the absence of oxygen, however, the fluorescence intensity markedly increases with temperature. At room temperature (25°C), and after degassing the sample, the fluorescence intensity of C70 increases 22 times, while at 100°C the fluorescence intensity is increased by 70 times. With our system, the very weak fluorescence of C70F ≅ 5 × 10−4, in toluene) can be increased up to 91 times (up to an estimated maximum value ΦF = 0.046). The estimate value of the singlet-triplet gap (29 kJ mol−1) and the fluorescence lifetime (0.63 ns) of the C70 in film are in agreement with the values reported in the literature for C70 in solution. The values of the phosphorescence lifetime at room temperature (23 ms) and the quantum yield of triplet formation (0.989) were also determined. The system is completely reversible with respect to heating-cooling cycles.

KEY WORDS:

Molecular fluorescence thermometry C70 thermally activated delayed fluorescence polystyrene film 

References

  1. 1.
    K. T. Grattan and Z. Y. Zhang (1995). Fiber Optic Fluorescence Thermometry, 1st ed., Chapman and Hall, London.Google Scholar
  2. 2.
    J. F. Lou, T. M. Finegan, P. Mohsen, T. A. Hatton, and P. E. Laibinis (1999). Fluorescence-based thermometry: principles and aplications. Rev. Anal. Chem. 18(4), 235–284.Google Scholar
  3. 3.
    A. J. Bur, M. G. Vandel, and S. C. Roth (2001). Fluorescence based temperature measurements and applications to real-time polymer processing. Polymer Eng. Sci. 41(8), 1380–1389.CrossRefGoogle Scholar
  4. 4.
    N. Chandrasekharan and L. A. Kelly (2001). A dual fluorescence temperature sensor based on perylene/exciplex interconversions. J. Am. Chem. Soc. 123(40), 9898–9899.PubMedCrossRefGoogle Scholar
  5. 5.
    S. Wang, S. Westcott, and W. Chen (2002). Nanoparticle luminescence thermometry. J. Phys. Chem. B 106(43), 11203–11209.CrossRefGoogle Scholar
  6. 6.
    Y. Amao and I. Okura (2002). Optical molecular thermometer based on the fluorescence of fullerene dispersed in poly(methyl methacrylate) film. Bull. Chem. Soc. Jpn. 75(2), 389–391.CrossRefGoogle Scholar
  7. 7.
    C. A. Parker (1968). Photoluminescence of Solutions, Elsevier, Amsterdam.Google Scholar
  8. 8.
    M. W. Wolf, K. D. Legg, R. E. Brown, L. A. Singer, and J. H. Parks (1975). Photophysical studies on the benzophenones. Prompt and delayed fluorescences and self-quenching. J. Am. Chem. Soc. 97(16), 4490–4497.CrossRefGoogle Scholar
  9. 9.
    A. M. Turek, G. Krishnammorthy, K. Phipps, and J. Saltiel (2002). Resolution of benzophenone delayed fluorescence and phosphorescence with compensation for thermal broadening. J. Phys. Chem. A 106(25), 6044–6052.CrossRefGoogle Scholar
  10. 10.
    A. Maciejewski, M. Szymanski, and R. P. Steer (1986). Thermally activated delayed S1 fluorescence of aromatic thiones. J. Phys. Chem. 90(23), 6314–6318.CrossRefGoogle Scholar
  11. 11.
    J. L. Kropp and W. R. Dawson (1967). Radiationless deactivation of triplet coronene in plastics. J. Phys. Chem. 71(13) 4499–4506.CrossRefGoogle Scholar
  12. 12.
    B. Nickel and D. Klemp (1993). The lowest triplet state of azulene-h 8 and azulene-d 8 in liquid solution. I. Survey, kinetic considerations, experimental technique, and temperature dependence of triplet decay. Chem. Phys. 174(2), 297–318.CrossRefGoogle Scholar
  13. 13.
    B. Nickel and D. Klemp (1993). The lowest triplet state of azulene-h 8 and azulene-d 8 in liquid solution: II. Phosphorescence and E-type delayed fluorescence. Chem. Phys. 174(2), 319–330.CrossRefGoogle Scholar
  14. 14.
    J. W. Arbogast and C. S. Foote (1991). Photophysical properties of C70. J. Am. Chem. Soc. 113(23), 8886–8889.CrossRefGoogle Scholar
  15. 15.
    S. M. Argentine, K. T. Kotz, and A. H. Francis (1995). Temperature and solvent effects on the luminescence spectrum of C70: Assignment of the lowest singlet and triplet states. J. Am. Chem. Soc. 117(47), 11762–11767.CrossRefGoogle Scholar
  16. 16.
    M. R. Wasielewski, M. P. O’Neil, K. R. Lykke, M. J. Pellin, D. M. Gruen (1991). Triplet states of fullerenes C60 and C70. Electron paramagnetic resonance spectra, photophysics, and electronic structures. J. Am. Chem. Soc. 113(7), 2774–2776.CrossRefGoogle Scholar
  17. 17.
    M. N. Berberan-Santos and J. M. M. Garcia (1996). Unusually strong delayed fluorescence of C70. J. Am. Chem. Soc. 118(39), 9391–9394.CrossRefGoogle Scholar
  18. 18.
    S. M. Bachilo, A. F. Benedetto, R. B. Weisman, J. R. Nossal, and W. E. Billups (2000). Time-resolved thermally activated delayed fluorescence in C70 and 1,2-C70H2. J. Phys. Chem. A 104(48), 11265–11269.CrossRefGoogle Scholar
  19. 19.
    F. A. Salazar, A. Fedorov, and M. N. Berberan-Santos (1997). A study of thermally activated delayed fluorescence in C60. Chem. Phys. Lett. 271(4–6), 361–366.CrossRefGoogle Scholar
  20. 20.
    B. Gigante, C. Santos, T. Fonseca, M. J. M. Curto, H. Luftmann, K. Bergander, and M. N. Berberan-Santos (1999). Diels-Alder adducts of C-60 and resin acid derivatives: Synthesis, electrochemical and fluorescence properties. Tetrahedron 55(19), 6175–6182.CrossRefGoogle Scholar
  21. 21.
    S. M. Anthony, S. M. Bachilo, and R. B. Weisman (2003). Comparative photophysics of C61H2 isomers. J. Phys. Chem. A 104(48), 10674–10679.CrossRefGoogle Scholar

Copyright information

© Springer Science+Business Media, Inc. 2006

Authors and Affiliations

  1. 1.Centro de Química-Física MolecularInstituto Superior TécnicoLisboaPortugal

Personalised recommendations