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Cooling Rate Dependent Ellipsometry Measurements to Determine the Dynamics of Thin Glassy Films
Published on: January 26, 2016
P3HT:PCBM blend films phase diagram on the base of variable-temperature spectroscopic ellipsometry
Barbara Hajduk1, Henryk Bednarski1, Bożena Jarząbek1
1Centre of Polymer and Carbon Materials, Polish Academy of Sciences, 34 Marie Curie-Skłodowska str., 41-819 Zabrze, Poland.
Abstract:
In this work we present an in-depth study of the how the composition of poly(3-hexylthiophene) (P3HT):[6,6]-phenyl-C61-butyric acid methyl ester (PCBM) blend films influences their phase transitions using variable-temperature spectroscopic ellipsometry. We demonstrate that this non-destructive method is a very sensitive optical technique to investigate the phase transitions and to determine the glass transition temperatures and melting crystallization points of the P3HT:PCBM blend films. By analyzing the influence of the temperature T on the raw ellipsometric data, we have identified a high sensitivity of the ellipsometric angle Δ at a wavelength of 280 nm to temperature changes. Characteristic temperatures determined from the slope changes of the Δ(T) plot appeared to be very good guess values for the phase transition temperatures.
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