Efficiency charge injection

Electron donor molecules are oxidized in solution easily. Eor example, for TTE is 0.33V vs SCE in acetonitrile. Similarly, electron acceptors such as TCNQ are reduced easily. TCNQ exhibits a reduction wave at — 0.06V vs SCE in acetonitrile. The redox potentials can be adjusted by derivatizing the donor and acceptor molecules, and this tuning of HOMO and LUMO levels can be used to tailor charge-transfer and conductivity properties of the material. Knowledge of HOMO and LUMO levels can also be used to choose materials for efficient charge injection from metallic electrodes. 

It is obvious that in an OLED efficient charge injection is crucial. A simple estimate will illustrate this. Suppose that a concentration n of charge carriers equivalent to the capacitor charge CV, where C is the capacitance per unit area and V is the applied voltage, is distributed homogeneously within a dielectric layer... 

Prussian Blue nanoparticles are in the close contact with the nanotube surface that would be helpful for efficient charge injection from CNTs-based electrodes into the PB... 

Although the setup required to induce electropolymerization is simple (Figure 2.2), the setup required to deliver a product of the necessary quality for real applications requires some thought and is still the subject of numerous studies. For example, in our own work,10 we have found that the use of concentric counter electrodes is essential to coat wire electrodes in a uniform fashion. In more recent work,11 we have verified the need for a helical wire interconnect to ensure efficient charge injection into hollow PPy fibers of micrometer dimensions but centimeters in length (Figure 2.3). 

One approach to this problem is to use heUcal wire windings that function as a more efficient charge injection route to polymer actuators (Figure 11.22) [144]. 

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