Signaling Recognition Events with Fluorescent Sensors and Switches.

Anion recognition chemistry has grown from its beginnings in the late 1960s with positively charged ammonium cryptand receptors for halide binding to, at the end of the millennium, a plethora of charged and neutral, cyclic and acyclic, inorganic and organic supramolecular host systems for the selective complexation, detection, and separation of anionic guest species. Solvation effects and pH values have been shown to play crucial roles in the overall anion recognition process. More recent developments include exciting advances in anion-templated syntheses and directed self-assembly, ion-pair recognition, and the function of anions in supramolecular catalysis.

Anion Recognition and Sensing: The State of the Art and Future Perspectives

Fluorogenic and chromogenic chemosensors and reagents for anions.

For more than 70 years, researchers in several areas of science have been intrigued by the physical and chemical properties of the lowest excited states of molecular oxygen. With two singlet states lying close above its triplet ground state, the O2 molecule possesses a very unique configuration, which gives rise to a very rich and easily accessible chemistry, and also to a number of important photophysical interactions. In particular, photosensitized reactions of the first excited state, O2(∆g), play a key role in many natural photochemical and photobiological processes, such as photodegradation and aging processes including even photocarcinogenesis. Reactions of O2(∆g) are associated with significant applications in several fields, including organic synthesis, bleaching processes, and, most importantly, the photodynamic therapy of cancer, which has now obtained regulatory approval in most countries for the treatment of several types of tumors. The development of both applications and novel observation techniques has strongly accelerated during the past few years. Significant recent advances include, for example, the development of novel luminescent singlet oxygen probes,1-4 the time-resolved detection of O2(∆g) in a transmission microscope,5 the first time-resolved measurements of singlet oxygen luminescence in vivo,6 and the observation of oxygen quenching of triplet-excited single molecules.7 Experimental and theoretical studies on the mechanisms of photosensitized formation of excited O2 states and of their deactivation have been performed for almost 40 years. While most early liquid-phase studies were exclusively concerned with O2(∆g), recent technological advances also made possible time-resolved investigations of the second excited state, O2(Σg), which can be formed in competition with O2(∆g) in many cases. A significant number of * Corresponding author. Tel.: ++49 69 79829448. Fax: ++49 69 79829445. E-mail: R.Schmidt@chemie.uni-frankfurt.de. 1685 Chem. Rev. 2003, 103, 1685−1757

Physical mechanisms of generation and deactivation of singlet oxygen.

This article concentrates on our recent results on several classes of photo- and electro-active organic materials that permit thin film formation and discusses their synthesis, properties, functions and potential applications for electronic and optoelectronic devices. The materials studied include amorphous molecular materials, titanyl phthalocyanine, oligothiophenes with well-defined structures, and non-conjugated polymers containing pendant oligothiophenes or other π-electron systems. The thin films of these materials find potential applications for use in organic electroluminescent, photovoltaic, electrochromic, and other devices.

Organic materials for electronic and optoelectronic devices

http://nathan.instras.com/MyDocsDB/doc-617.pdf

Electrochromic organic and polymeric materials for display applications

Many inorganic and organic materials exhibit redox states with distinct electronic (UV-vis) absorption bands. When the switching of redox states generates new or different visible region bands, the material is electrochromic. Electrochromic materials are currently attracting much interest in academia and industry for both their fascinating spectroelectrochemical properties and their commercial applications. In this review some of the most important examples from the major classes of electrochromic materials are highlighted. Examples of their use in both prototype and commercial electrochromic devices are illustrated including car mirrors, windows and sun-roofs of cars, windows of buildings, displays (see Figure), printing, and frozen-food monitoring.

Electrochromic Systems and the Prospects for Devices

Part 1 Introduction: electrochromism - what is electrochromism?, existing technologies, electrochromic displays and shutters, terminology of electrochromism, primary and secondary electrochromism, colour and contrast ratio, colouration efficiency, write-erase efficiency, response time, cycle life, the insertion coefficient, ECD appearance electrochromic systems -equilibrium electrochemistry, electrochromic operation exemplified, voltammetry, charge transfer and charge transport, AC or RF electrochemistry, electrodes construction of electrochromic devices -all-solid cells with reflective operation, all-solid cells with transmissive operation, solid electrolytes, the preparation of solid electrochromic films, liquid electrolytes, self-darkening electrochromic rearview mirror for cars employing type 1 (solution-phase) electrochromes. Part 2 Electrochromic systems: metal oxides-cobalt oxide, indium tin oxide, iridium oxide, molybdenum trioxide, nickel oxide, tungsten trioxide, vanadium pentoxide, other metal oxides, mixed metal oxides, metal oxide - organic mixtures phthalocyanine compounds - lutetium bis(phthalocyanine), other metal phthalocyanines, related species prussian blue - preparation of prussian blue thin films, prussian blue electrochromic films, prussian blue ECDs, prussian blue analogues other inorganic systems - deposition of metals, deposition of colloidal material, intercalation layers, inclusion and polymeric systems bipyridilium systems - bipyridilium redox chemistry, bipyridilium species for inclusion within ECDs, recent developments electroactive conducting polymers - polyaniline electrochromes, polypyrrole electrochromes, polythiophene electrochromes, poly(carbazole), miscellaneous polymeric electrochromes, recent developments other organic electrochromes - monomeric species, tethered electrochromic species, electrochromes immobilised by viscous solvents polyelectrochromism - studies of polyelectrochromic systems photoelectrochromism and electrochromic printing - device types, electrochromic printing or electrochromography.

Electrochromism : fundamentals and applications

A number of inorganic and organic materials exhibit redox states (reduced and/or oxidised forms) with distinct UV-Visible (electronic) absorption bands. When electrochemical switching of these redox states gives rise to different colours (i.e. new or different visible region bands), the material is described as being electrochromic. By virtue of their numerous applications, both of academic and commercial interest, electrochromic materials are currently attracting a great deal of interest. This review provides an introduction to the major classes of electrochromic materials, namely transition metal oxides, Prussian blue systems, viologens, conducting polymers, transition metal and lanthanide coordination complexes and metallopolymers, and metal phthalocyanines. Examples of some new materials and of prototype and commercial electrochromic devices are cited.

/pdf/new-electrochromic-materials-2sst279q56.pdf

New Electrochromic Materials

http://nathan.instras.com/documentDB/paper-257.pdf

Roger J. Mortimer

Papers

Electrochromic organic and polymeric materials for display applications

Electrochromic Systems and the Prospects for Devices

Electrochromism : fundamentals and applications

New Electrochromic Materials

Organic electrochromic materials