Properties opto-electronic

The science and technology of conducting polymers are inherently interdisciplinary they fall at the intersection of three established disciplines chemistry, physics and engineering hence the name for this volume. These macromolccular materials are synthesized by the methods of organic chemistry. Their electronic structure and electronic properties fall within the domain of condensed matter physics. Efficient processing of conjugated polymer materials into useful forms and the fabrication of electronic and opto-electronic devices require input from engineering i. e. materials science (more specifically, polymer science) and device physics. 

Optical properties, of colorless polyimides, 277-279 Optical rotation, 490 Opto-electronic targets, 271-272 Organic phase-soluble aromatic polyesters, 77... 

The many possible combinations of II-V and II-VI compounds allow the tailoring of electronic and opto-electronic properties to suit specific applications. Of particular importance is the control of the stoichiometry of the element involved. This is achieved by the proper handling of the MOCVD reactions. Being able to tailor the bandgap imparts great flexibility in the design of transistors and optoelectronic devices. 

Conceptually and synthetically more straightforward molecules can be prepared through incorporation of chromophores onto simple phosphine moieties. The phosphorus fragment can be used either to influence or to organise the n-con-jugated systems. This section will focus only on derivatives tailored in order to exhibit specific properties related to applications in NLO,opto-electronics or as sensors. 

The opto-electronic properties of branched structures have been an area of some interest for a number of years, especially as NLO and light-emitting materials [82]. In particular, the use of u-conjugated dendrimers (mono-disperse macromolecules [83]) has flourished for a number of reasons ... 

Grozema FC, Siebbeles LDA, Gelinck GH, Warman JM (2005) The Opto-Electronic Properties of Isolated Phenylenevinylene Molecular Wires. 257 135-164 Guiseppi-Elie A, Lingerfelt L (2005) Impedimetric Detection of DNA Hybridization Towards Near-Patient DNA Diagnostics. 260 161-186 Guo Y, see Coleman AW (2007) 277 31-88... 

Polycrystalline GaN UV detectors have been realized with 15% quantum efficiency [4], This is about 1 /4 of the quantum efficiency obtained by crystalline devices. Available at a fixed price, however, their increased detection range may well compensate their lack in sensitivity. Furthermore, new semiconductor materials with a matching band gap appear as promising candidates for UV detection if the presumption of the crystallinity is given up. Titanium dioxide, zinc sulfide and zinc oxide have to be mentioned. The opto-electronic properties and also low-cost production processes for these compound semiconductors have already been investigated to some extent for solar cell applications [5]. 

The highly oriented molecules in thin organic films such as Langmuir-Blodgett (LB) films and self-assembled monolayers (SAM) [1] are essential for some molecular functions. Non linear optical and opto-electronic properties are two of the most important and interesting functions of these molecular assemblies. In the past more than thirteen years, simulation of the primary process of photosynthesis using such molecular assemblies and its application to molecular photodiodes [2,3] have been one of the main subjects of our laboratory. 

Abstract This review highlights how molecular Zintl compounds can be used to create new materials with a variety of novel opto-electronic and gas absorption properties. The generality of the synthetic approach described in this chapter on coupling various group-IV Zintl clusters provides an important tool for the design of new kinds of periodically ordered mesoporous semiconductors with tunable chemical and physical properties. We illustrate the potential of Zintl compounds to produce highly porous non-oxidic semiconductors, and we also cover the recent advances in the development of mesoporous elemental-based, metal-chalcogenide, and binary intermetallic alloy materials. The principles behind this approach and some perspectives for application of the derived materials are discussed. 

The metal-ligand fragment L M, the number of carbon atoms x, and the substituents at the terminal sp -carbon may vary considerably and, correspondingly, the properties and reactivities. The early members of the series of cumulenylidene complexes (x=l, 2, 3 carbene, vinylidene and allenylidene complexes) have established themselves as invaluable building blocks in stoichiometric synthesis and as highly potent catalyst precursors. The higher members might potentially be very useful candidates for application as one-dimensional wires and in opto-electronic devices. 

Because of the limitations of both electronics and photonics a hybrid technology, opto-electronics, has been a major area of research since the 1980s, especially into the non-linear properties of molecules and their potential applications in communications, data storage and information processing. ... 

Exploitation of these is possible in LEDs that display coherence properties, in thresholdless laser diodes, and in many other optical, opto-electronic and quantum electronic devices. 

The examples of polyacetylenes whose main chain is directly bonded to heteroaromatic rings (e.g., silole, carbazole, imidazole, tetrathiafulvalene, ferrocene) are increasing in number. Such polymers are usually obtained by one of catalysts (W, Mo, and Rh). The formed polymers are expected to display interesting (opto)electronic properties such as electrochromism, cyclic voltammetry, electroluminescence, and so on. 

Various crystalline materials with desired properties have been synthesized, and this has driven the utilization of single crystals in the production of semiconductor, opto-electronic, piezoelectric, and pyroelectric materials. 

Tacticity is required for the synthesis of crystalline thin polysilane films used for optical and semiconductor devices. Modern synthetic routes allow control over the conformation and tacticity of polysilane molecules used as precursors for thin layers of photoresists, photoconductors and nonlinear optical phases in complex semiconductor and (opto)electronic devices. These properties can be exploited only if the synthesis method ensures a minimal level of contamination, especially with oxygen and metals, and special care is taken to limit electronic-grade polysilanes to a level of contamination on the order of a few ppm in the case of oxygen and in the ppb range for metals. The reactivity of polysilane toward oxygen has forced placing the devices in a helium environment during measurement procedures.36... 

SOURCE Reprinted from de Boer, B., U. Stalmach, P. F. van Hutten, C. Melzer, V.V. Krasnikov, and G. Hadziioannou. 2001. Supramolecular self-assembly and opto-electronic properties of semiconducting block copolymers. Polymer 42 9097-9109. Copyright 2001 with permission from Elsevier. 

Applications of conjugated polymers-NCs hybrids in various (opto-)electronic devices and sensors require a deeper understanding of the relationship between their chemical and photophysical properties and their structure at different levels from the molecular to the bulk material. This requires the use of complementary methods... 

Grozema FC, Siebbeles LDA, Gelinck GH, Warman JM (2005) The Opto-Electronic Properties of Isolated Phenylenevinylene Molecular Wires. 257 135-164... 

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