Organic/polymer light-emitting diodes OLEDs/PLEDs

When 3,4-ethylenedioxythiophene (EDOT) is chemically polymerized in the presence of polyacrylic acid (PAA) as a template, conducting nanowires can be assembled from smaller nanowires in a side-by-side manner and exhibit excellent conductivity [115]. The electronic properties of PTh have promoted a wide interest in the development of organic/polymer light-emitting diodes (OLEDs/PLEDs) and it is note worthy that the performance of these devices is dramatically enhanced by the... 

As a class of n-type organic semiconductors, PBI derivatives have received considerable attention for a variety of applications [312, 313], for example, for organic or polymer light-emitting diodes (OLEDs and PLEDs) [314, 315], thin-film organic field-effect transistors (OFETs) [316, 317], solar cells [318, 319], and liquid crystals [320]. They are also interesting candidates for single-molecule device applications, such as sensors [321], molecular wires [322], or transistors [141]. 

Organic Light-Emitting Diodes (OLED) and Polymer Light-Emitting Diodes (PLED) based on the mechanism foreseen by Marcus have been realized in practice. PLEDs are successively formed from an Al, Mg or Ca cathode, an organic conductive polymer and an ITO (Indium, Tin, Oxide) anode, as schematically illustrated in Fig. 36.31. 

Additionally, the film formation properties and outstanding mechanical properties of aramids make these polymers suitable for the production of organic light emitting diodes (OLEDs), and specifically polymer hght emitting diodes (PLEDs). Despite this, classical condensation polymers are rarely studied for these applications. Moreover, some luminescence materials also show electrochromism (EC), a phenomenon in which materials exhibit a reversible change in optical properties when they are oxidized and reduced. Electrochromic materials are now been exploited in diverse applications such as mirrors, displays, windows, and earth-tone chameleon materials [95]. 

We saw in Chapter 20 that some organic molecules and polymers can be doped to make them either p-type or n-type semiconductors. Therefore, it should be possible to make a p-n junction and, if there is a direct bandgap, it should also be possible to make a small molecule organic light-emitting diode (OLED) and a polymer light-emitting diode (PLED). 

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