Journal of Materials Science

, Volume 50, Issue 20, pp 6677–6687 | Cite as

Thermo-optic properties of hybrid sol–gel thin films doped with Rhodamine 6G at high vacuum conditions

  • Pilar García ParejoEmail author
  • Alberto Alvarez-Herrero
  • Marcos Zayat
  • David Levy
Original Paper


An inorganic–organic hybrid thin film doped with Rhodamine 6G prepared by the sol–gel technique has been studied at thermal vacuum conditions by variable angle spectroscopic ellipsometry in order to assess the suitability of using these films in aerospace applications. The thermo-optic properties of the Rhodamine 6G-doped thin film, i.e., the thermo-optic coefficient dn/dT (dependence of the refractive index on temperature) and its linear thermal expansion coefficient α (dependence of the thickness of the film on temperature) were studied in the 343–77 K temperature range obtaining a negative thermo-optic coefficient of −5 × 10−5 K−1 and a linear thermal expansion α of 5.8 × 10−5 K−1. The stability of the Rhodamine 6G molecules in the sol–gel matrix was studied at 303, 323, and 343 K at high vacuum (10−6 mbar) and no significant outgassing or thermal decomposition of the Rhodamine 6G molecules were found, which assures the performance of the hybrid thin films at high vacuum conditions up to the temperature of 343 K. The spectroscopic properties of the Rhodamine 6G molecules showed a dependence on temperature based on a Boltzmann distribution of the vibrational and rotational energy levels that was characterized in the 343–77 K temperature range. We have found that both the hybrid sol–gel thin film and the embedded Rhodamine 6G molecules successfully withstand the extreme temperatures and high vacuum studied, which make these materials promising components for space missions and open new opportunities for the usage of the hybrid sol–gel materials in the aerospace industry.


Thermal Contraction Linear Thermal Expansion Coefficient High Vacuum Condition Ellipsometric Measurement Complex Dielectric Function 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.



The authors are grateful to MINECO for the research Grant: MAT2011-28981.

Compliance with Ethical Standards

Conflict of interest

The authors declare that they have no conflict of interest associated with this publication.


  1. 1.
    Costela A, García-Moreno I, Gómez C, García O, Sastre R (2002) New organic-inorganic hybrid matrices doped with rhodamine 6G as solid-state dye lasers. Appl Phys B 75:827–833CrossRefGoogle Scholar
  2. 2.
    Garcia-Revilla S, Fernández J, Illaramendi MA, García-Ramiro B, Balda R, Cui H, Zayat M, Levy D (2008) Ultrafast random laser emisión in a dye-doped silica gel powder. Opt Express 16:12251–12263CrossRefGoogle Scholar
  3. 3.
    Weber WH, Lambe J (1977) Materials for luminiscent greenhouse solar collectors. Appl Opt 16:2684–2689CrossRefGoogle Scholar
  4. 4.
    Reisfeld R (2002) Fluorescent dyes in sol-gel glasses. J Fluoresc 12:317–325CrossRefGoogle Scholar
  5. 5.
    Sun JW, Jeong-Hwan L, Chang-Ki M, Kwon-Hyeon K, Shin H, Jang-Joo K (2014) A fluorescent organic light-emitting diode with 30 % external quantum efficiency. Adv Mater 26:5684–5688CrossRefGoogle Scholar
  6. 6.
    Pardo R, Zayat M, Levy D (2005) The influence of sol-gel processing parameters on the photochromic spectral and dynamic behaviour of a naphthopyran dye in an ormosil coating. J Mater Chem 15:703–708CrossRefGoogle Scholar
  7. 7.
    Coelho PJ, Silva CJR, Sousa C, Moreira SDFC (2013) Fast and fully reversible photochromic performance of hybrid sol-gel films doped with a fused-naphthopyran. J Mater Chem C 1:5387–5394CrossRefGoogle Scholar
  8. 8.
    Levy D, Pena JMS, Serna CJ, Otón JM (1992) Glass dispersed liquid crystals for electro-optica devices. J Non-Cryst Solids 147:646–651CrossRefGoogle Scholar
  9. 9.
    Ohyama T, Maruo YY, Tanaka T, Hayashi T (1999) Fluorescence-intensity changes in organic dyes impregnated in porous glass on exposure to NO2. Sens Actuators B 59:16–20CrossRefGoogle Scholar
  10. 10.
    Gupta R, Chaudhury NK (2007) Entrapment of biomolecules in sol-gel matrix for applications in biosensors: problems and future prospects. Biosens Bioelectron 22:2387–2399CrossRefGoogle Scholar
  11. 11.
    McEvoy AK, McDonangh CM, MacCraith BD (1995) Development of a fibre-optic disolved oxygen sensor based on quenching of a ruthenium complex entrapped in a porous sol-gel film. Proc SPIE 2508:190–198CrossRefGoogle Scholar
  12. 12.
    MacCraith BD, McDonagh CM, O’Keeffe G, McEvoy AK, Butler T, Sheridan FR (1995) Sol-gel coatings for optical chemical sensors and biosensors. Sens Actuators B 29:51–57CrossRefGoogle Scholar
  13. 13.
    Mujahid A, Lieberzeit PA, Dicket FL (2010) Chemical sensors based on molecularly imprinted sol-gel materials. Materials 3:2196–2217CrossRefGoogle Scholar
  14. 14.
    Carmona N, Herrero E, LLopis J, Villegas MA (2007) Chemical sol-gel-based sensors for evaluation of environmental humidity. Sens Actuators 126:455–460CrossRefGoogle Scholar
  15. 15.
    Kazemi AA (2008) Fiber optic microsensor technology for detection of hydrogen in space applications. In: Proceedings of SPIE 7003:70032E-1–70032E-9Google Scholar
  16. 16.
    Kazemi AA, Mendoza E, Goswami K, Kempen L (2013) Fiber optic oxygen sensor detection systems for harsh environments of aerospace applications. Proc SPIE 8720:872002-1–872002-14Google Scholar
  17. 17.
    Pisacane VL (2005) Fundamental of space systems, JHU/APL series in science and engineering. Oxford University Press, OxfordGoogle Scholar
  18. 18.
    Ferreira LFV, Branco TJF, do Rego AB (2004) Luminiscence quantum yield determination for molecules adsorbed onto solid powdered particles. Chem Phys Chem 5:1848–1854Google Scholar
  19. 19.
    Azzam RMA, Bashara NM (2003) Ellipsometry and polarized Light. North-Holland Personal Library Elsevier, AmsterdamGoogle Scholar
  20. 20.
    Fujiwara H (2007) Spectroscopic ellipsometry principles and applications. Wiley, ChichesterCrossRefGoogle Scholar
  21. 21.
    Weber JW, Calado VE, van de Sanden MC (2010) Optical constants of graphene measured by spectroscopic ellipsometry. Appl Phys Lett 95:091904CrossRefGoogle Scholar
  22. 22.
    Meyer F, Bootsma GA (1969) Ellipsometric investigation of chemisorption on clean silicon (111) and (100) surfaces. Surf Sci 16:221–233CrossRefGoogle Scholar
  23. 23.
    den Engelsen D, de Koning B (1974) Ellipsometry of spread monolayers. Part 2 Coloured systems: chlorophyll a, caretonic acid, rhodamine 6G and a cyanine dye. J Chem Soc Faraday Trans 1(70):2100–2112CrossRefGoogle Scholar
  24. 24.
    Jackson JD (1975) Classical electrodynamics. Wiley, New YorkGoogle Scholar
  25. 25.
    Press WH, Teukolsky SA, Vetterling WT, Flannery BP (1988) Numerical recipes in C: the art of scientific computing, 2nd edn. Cambridge University Press, CambridgeGoogle Scholar
  26. 26.
    Alvarez-Herrero A, Pardo R, Zayat M, Levy D (2007) Ellipsometric analysis of the spectral properties and dynamic transitions of photochromic thin films. J Opt Soc Am B 24:2097–2107CrossRefGoogle Scholar
  27. 27.
    Lu Y, Penzkofer A (1986) Absorption behaviour of methanolic rhodamine 6G solutions at high concentration. Chem Phys 107:175–184CrossRefGoogle Scholar
  28. 28.
    Parvathy Rao A, Venkateswara Rao A (2003) Luminiscent dye Rhodamine 6G monolithic and transparent TEOS silica xerogels and spectral properties. Sci Technol Adv Mater 4:121–129CrossRefGoogle Scholar
  29. 29.
    Weininger H, Schmidt J, Penzkofer A (1989) Absorption spectroscopic investigation of rhodamine dye vapors. Chem Phys 130:379–387CrossRefGoogle Scholar
  30. 30.
    Prod’homme L (1960) A new approach to the thermal change in the refractive index of glasses. Phys Chem Glasses 4:119–122Google Scholar
  31. 31.
    Eun-Seok K, Tae-Ho L, Byeong-Soo B (2002) Measurement of the thermo-optic coefficients in sol-gel derived inorganic-organic hybrid material films. Appl Phys Lett 81:1440–1448Google Scholar
  32. 32.
    Pokrass M, Burshtein Z, Gvishi R (2010) Thermo-optic coefficient in some hybrid organic/inorganic fast sol-gel glasses. Opt Mater 32:975–981CrossRefGoogle Scholar
  33. 33.
    Jewell JM (1991) Thermooptic coefficients of some standard reference material glasses. J Am Ceram Soc 74:1689–1691CrossRefGoogle Scholar
  34. 34.
    Eun-Seok K, Woo-Soo K, Kwang-Soo K, Byeong-Soo B (2004) Modification of thermo-optic characteristics of sol-gel inorganic-organic hybrid materials. J Sol-Gel Technol 32:277–280CrossRefGoogle Scholar
  35. 35.
    Eun-Seok K, Jang-Ung P, Byeong-Soo B (2003) Effect of organic modifiers on the thermo-optic characteristics of inorganic-organic hybrid material films. J Mater Res 18:1880–1894Google Scholar
  36. 36.
    Soave PA, Dau RAF, Becker MR, Pereira MB, Horowitz F (2009) Refractive index control in bicomponent polymer films for integrated thermo-optical applications. Opt Eng 48:124603-1–124603-6CrossRefGoogle Scholar
  37. 37.
    Sauer M, Hoftens J, Enderlein J (2011) Handbook of fluorescence spectroscopy and imaging. Wiley, New YorkCrossRefGoogle Scholar
  38. 38.
    Hinckley DA, Seybold PG, Borris DP (1986) Solvatochromism and thermochromism of rhodamine solutions. Spectrochim Acta 42A:747–754CrossRefGoogle Scholar
  39. 39.
    Selwyn JE, Steinfeld JI (1972) Aggregation equilibria of xanthene dyes. J Phys Chem 76:762–774CrossRefGoogle Scholar

Copyright information

© Springer Science+Business Media New York 2015

Authors and Affiliations

  • Pilar García Parejo
    • 1
    Email author
  • Alberto Alvarez-Herrero
    • 1
  • Marcos Zayat
    • 2
  • David Levy
    • 2
  1. 1.Laboratorio de Instrumentación Espacial (LINES)Instituto Nacional de Técnica Aeroespacial (INTA)MadridSpain
  2. 2.Sol-Gel Group (SGG)Instituto de Ciencia de Materiales de Madrid (ICMM-CSIC)MadridSpain

Personalised recommendations