Nematic photovoltaics

On the other hand, miscibility is, in one sense, one of the characteristic properties in liquid crystals. Miscibility in liquid crystals is a well-known macroscopic property where one can see two mesogens exhibiting a thermodynamically identical liquid crystalline phase are mixed to show its phase at arbitrary component ratio. This has already been applied to liquid crystals for LCDs to control some properties such as temperature range of nematic phase. A diversity of functional properties such as temperature range, anisotropic electrical permittivity, viscosity etc. can be controlled in nematic blends and non-mesogenic molecules also can be a component which contributes to the resultant properties as they behave like a solute in liquid solution. However, charge transport property has not yet been well studied in terms of molecular blends with liquid crystalline materials, while thin film organic photovoltaics have been so extensively studied in recent years as molecular blends. 

Carrasco-Orozco, M., et al. New photovoltaic concept, liquid-crystal solar cells using a nematic gel template. Adv. Mater. 18(13), 1754-1758 (2006)... 

Tsoi, W.C., et al. Distributed bUayer photovoltaics based on nematic liquid crystal polymer networks. Chem. Mater. 19(23), 5475-5484 (2007)... 

In 1972 the photovoltaic effect was first demonstrated in devices with nematic liquid crystals by means of ionic conduction [36]. Although electronic charge transport was widely researched in these materials [37, 38], it was not until 2006 that electronic conduction was first applied to photovoltaics in nematics [39]. A novel approach based on reactive mesogens was used to create a D-A bilayer with a distributed interface. Reactive mesogens are polymerisable equivalents of small molecule LCs, but with two additional polymerisable groups, one at each end of a flexible aliphatic spacer attached to the aromatic core. Chapters 2 and 5 discusses charge transport in these materials. Figure 8.8 illustrates the photopolymerisation of such molecules. 

Kamei, H., Ozawa, X., Katawama, Y. Photovoltaic effect in the nematic liquid crystal. Jpn. J. Appl. Phys. 11, 1385 (1972)... 

A1 Khalifah, M.S. Nematic liquid crystals for nanostructured organic photovoltaic. PhD thesis. The University of Hull (2010)... 

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