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Charge Transport Properties of a Metal-free Phthalocyanine Discotic Liquid Crystal

C. Deibel·D. Janssen·P. Heremans·V. de Cupere·Y. Geerts·M. L. Benkhedir·G. J. Adriaenssens
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Abstract

Discotic liquid crystals can self-align to form one-dimensional semiconducting wires, many tens of microns long. In this letter, we describe the preparation of semiconducting films where the stacking direction of the disc-like molecules is perpendicular to the substrate surface. We present measurements of the charge carrier mobility, applying temperature-dependent time-of-flight transient photoconductivity, space-charge limited current measurements, and field-effect mobility measurements. We provide experimental verification of the highly anisotropic nature of semiconducting films of discotic liquid crystals, with charge carrier mobilities of up to 2.8x10$^{-3}$cm$^2$/Vs. These properties make discotics an interesting choice for applications such as organic photovoltaics.

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C. Deibel, D. Janssen, P. Heremans, V. de Cupere, Y. Geerts, M. L. Benkhedir, G. J. Adriaenssens. 2006-07-14. Charge Transport Properties of a Metal-free Phthalocyanine Discotic Liquid Crystal. https://doi.org/10.1016/j.orgel.2006.07.002

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