Transport electron and hole

PWM Blom, MJM de Jong, and JJM Vleggaar, Electron and hole transport in poly(p-phenylene) devices, Appl. Phys. Lett., 68 3308-3310, 1996. 

Electron and hole migration through the electron and hole transport layers... 

Once the electrons and holes have been injected, they migrate into ETL and HTL to form excited states referred to as polarons by physicists or radical ions by chemists. These polarons or radical ions move, by means of a so-called charge-hopping mechanism, through the electron and hole transport materials (ETMs and HTMs), which typically possess good charge mobility properties, and eventually into the EML. 

Blakesley JC, Clubb HS, Greenham NC (2010) Temperature-dependent electron and hole transport in disordered semiconducting polymers analysis of energetic disorder. Phys Rev B 81 045210... 

Finally, we point out that there is a close relation in description of ion electro-diffusion and the phenomenological theory of the electron and hole transport in semiconductors. In order to facilitate the reading we present below a brief ionics-semiconductor vocabulary. ... 

We have discussed the effects of chemisorption and of electron and hole transport across the semiconductor/electrolyte interface. These have been shown to play a large role in determining electrode properties. Recently another mechanism of... 

The bipolar single-trap model assumes that both electrons and holes share identical trap centers. Since sequential trappings of the electrons and holes by the identical centers mean the neutralization of the electric charge, the effective space-charge field will depend on the relative power (i.e., the mobilities) of electron and hole transports. The expressions for the writing and erasing diffraction efficiency are [100] ... 

Subsequently, Cao et al. incorpated electron and hole transporting groups on to the zinc(II) Schiff base polymer chain for PLEDs application (Fig. 21).35 Fluorene and carbazole-containing polymers were prepared by reacting the... 

Mort and Emerald (1974) measured hole mobilities of TNF PVK mixtures. The results were in qualitative agreement with those by Gill. The field dependencies were described by a power-law relationship. It was concluded that electron and hole transport states were associated with TNF and carbazole pen-... 

The general features of electron and hole transport in polymers and doped polymers are similar. The mobilities are very low, strongly field and temperature dependent, as well as dependent on the dopant molecule, dopant concentration, and the polymer host. Despite the similarities, however, there are significant differences. 

Just as described for LEDs in the preceding section, the area of the heterojunction in solar cells with the planar structure shown in Fig. 10.3(a) is defined by the dimensions of the cell. Similarly, this area is dramatically increased by the use of blends of immiscible electron- and hole-transporting polymers (Moons, 2002). Carriers generated at the dispersed interface between the two polymers will be able to diffuse to the electrodes if the network contains... 

A 7i-conjugated systems is a molecule along the backbone of which occurs a continuous path of carbon atoms or heteroatoms, each carrying a p atomic orbital. The determination of the electronic structure of conjugated systems and their properties in terms of energy, electron and hole transport is very difficult. Electron correlation effects must be taken into account and the strong connection between, and mutual influence of, the electronic and geometric structures should be evaluated [91]. 

Figure 1.3 Typical ETA cell geometries. The interfaces between the absorber and electron and hole transport layers are structured, usually in porous (Fig. 1.3a) or columnar (Fig. 1.3b) form. The interfaces between the transport layers and the contact layers are planar. If the substrate morphology is porous, both transport layers should be transparent to avoid shadowing effects. The contact layer on the light entry side must be transparent and the back contact should be reflective, to minimise optical losses outside the absorber layer. If the interfacial structuring is not very deep, it is possible to omit the hole transport layer, and deposit the back contact straight onto the ETA layer, which greatly simplifies device fabrication.

The double-strand structure of an oligonucleotide is shown schematically in Fig. 6-1. Anticipating discussion in later Sections, the molecule is shown in a upright orientation attached to an atomically planar metallic electrode surface (Au(lll), cf below) by chemisorption via a hexamethylenethiol group. Fig. 6-1 shows the four nucleobases presently in focus. We discuss first concepts and formalism of electron and hole transport of DNA-based molecules in homogeneous solution and at electrochemical interfaces. We then focus on DNA-based molecules in electrochemical nanogaps and STM in electrochemical environments in situ STM). Some case examples illustrate accordance and limitations of current theoretical views of DNA-conductivity. This adds to the comprehensive overview of interfacial electrochemical ET of DNA-based molecules by O Kelly and Hill in Chapter 5. 

A maximum luminance value of about 90000 cd/m at 1300 mA/cm was reached for 13 and of about 90000 cd/m at a similar current density for 2. The good performance of the devices was likely to be related to a much better balance of electron- and hole-transport properties than that achieved with linear or V-shaped oligothiophene-S,S-dioxides. 

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