Conjugated polymers PLEDs

The simplest light-emitting devices with conjugated polymers (PLEDs) are realized in such a manner that the polymer is arranged between two metal electrodes (see Figs. 30.7 and 30.8) [6,10]. The mechanism of the charge carrier injection into the polymer is discussed later in this section and in Section IV, whereas the... 

Section 1.2 gives a brief review of conjugated polymers in semiconducting and metallic phases. Section 1.3 discusses device architectures and their corresponding processes. Section 1.4 introduces some novel devices and their functions in thin-film polymer devices. Section 1.5 is devoted to technical merits of SMOLEDs and PLEDs used as emitter elements in flat-panel displays. 

Although the exact mechanism of the fluorenone formation is not known, it is believed that the monoalkylated fluorene moieties, present as impurities in poly(dialkylfluorenes), are the sites most sensitive to oxidation. The deprotonation of rather acidic C(9)—H protons by residue on Ni(0) catalyst, routinely used in polymerization or by metal (e.g., calcium) cathode in LED devices form a very reactive anion, which can easily react with oxygen to form peroxides (Scheme 2.26) [293], The latter are unstable species and can decompose to give the fluorenone moiety. It should also be noted that the interaction of low work-function metals with films of conjugated polymers in PLED is a more complex phenomenon and the mechanisms of the quenching of PF luminescence by a calcium cathode was studied by Stoessel et al. [300],... 

Apart from the tunable color emission covering the full visible range, there are several other aspects supporting the interest in PTs for PLEDs. PTs are examples of classical conjugated polymers with intrinsic one-dimensionality of the polymer chain. Alignment can induce anisotropy in macroscopic properties such as electron transport or optical properties. Polarized... 

Just as with other conjugated polymers, the emission color of PPE can be tuned by introducing different conjugated fragments in the polymer chain (copolymers 523 and 524) [627,638], Thus, red-orange EL (AEL 590 nm and a shoulder at 530 nm) was reported for the anthracene-based polymer 523 (in PLED ITO/523/A1), whereas... 

R.E. Martin, F. Geneste, and A.B. Holmes, Synthesis of conjugated polymers for application in light-emitting diodes (PLEDs), C.R. Acad. Sci. Paris, t. 1, Serie IY 447 -70, 2000. 

The main drawback of the PLED device with jt-conjugated polymers is that there is an imbalance between the rate of electrons and hole injection near the interface between the polymer and the cathode. Many approaches have been proposed to improve the performance of the devices such as using... 

Rational Design of High-Performance Conjugated Polymers for PLEDs... 

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