Scientists at Kyushu University in Japan have reported liquid-OLED in a recent issue of Applied Physics Letters.
In cells sandwiched between sheets of glass - much like an LCD - Denghui Xu and Chihaya Adachi mixed hole carrier ethylhexyl carbazole with rubrene which is both an electron carrier and photoemitter.
The researchers observed electroluminescence from rubrene with the naked eye, according to PhysOrg.com.
The paper, "Organic light-emitting diode with liquid emitting layer", is in Applied Physics Letters 95, 053304 (2009).
See also: Electronics Weekly's roundup of content related to LEDs, with a special focus on both white LEDs and coloured LEDs:
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