Controlling bulk aggregation state in semiconducting conjugated polymer solution

Chi-Chung Hua; Chih-Yuan Kuo; Show-An Chen
September 2008
Applied Physics Letters;9/22/2008, Vol. 93 Issue 12, p123303
Academic Journal
Dynamic light scattering measurements disclosed the ubiquity of large aggregate species (i.e., generally above 100 nm in hydrodynamic radius) in the precursor solutions customarily used to fabricate polymer-based light-emitting diodes (PLEDs). Transformation of these species into nanoscale thin films is expected to influentially interfere with the performance of the fabricated PLEDs. Controlling these large aggregate species was noticed to require strategies at variance with the convectional ones of controlling the more localized aggregation state. The present observations suggest that compromising the bulk and the local solution aggregation states is essential in producing tunable and high-performance PLEDs.


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