Polymer-based hole-transport materials

To fabricate multilayer pol5mier light-emitting diodes using solution processes, extensive efforts have been invested in developing new 

F ure 5.9. Structure of the cross-linkable polymers poly8-10, polylS and polyl4 

Regarding the number of layers, this woik brilliantly demonstrated that no limit exists and that up to four layers can be cross-linked. As last appealing feature, authors demonstrated that the whole process could even work in air, which dramatically simplifies OLED fabrication from the manufacturing point of view. 

Notably, devices comprising the functional ED photoresists reached a maximum CE of 7.87 cd/A, far from the 3.60 cd/A obtained with the 

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Gebeyehu, D., et al. 2002. Hybrid solar cells based on dye-sensitized nanoporous Ti02 electrodes and conjugated polymers as hole transport materials. Synth Met 125 279. 

A solid-state solar cell was assembled with an ionic liquid—l-ethyl-3-methylimidazolium bis(trifluoromethanesulfone)amide (EMITFSA) containing 0.2 M lithium bis(trifluoromethanesulfone)amide and 0.2 M 4-tert-butylpyridine—as the electrolyte and Au or Pt sputtered film as the cathode.51,52 The in situ PEP of polypyrrole and PEDOT allows efficient hole transport between the ruthenium dye and the hole conducting polymer, which was facilitated by the improved electronic interaction of the HOMO of the ruthenium dye and the conduction band of the hole transport material. The best photovoltaic result ( 7p=0.62 %, 7SC=104 pA/cm2, FOC=0.716 V, and FF=0.78) was obtained from the ruthenium dye 5 with polypyrrole as the hole transport layer and the carbon-based counterelectrode under 10 mW/cm2 illumination. The use of carbon-based materials has improved the electric connectivity between the hole transport layer and the electrode.51... 

Jiang, X., Liu, S., Liu, M., Herguth, P, Jen, A.Y., Pong, H., Sarikaya, M., 2002. Perfluorocyclobutane-based arylamine hole-transporting materials for organic and polymer light-emitting diodes. Adv. Punct. 

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