Electrochromism

About: Electrochromism is a(n) research topic. Over the lifetime, 13097 publication(s) have been published within this topic receiving 294637 citation(s).

Generalized synthesis of periodic surfactant/inorganic composite materials

Abstract: THE recent synthesis of silica-based mesoporous materials1,2 by the cooperative assembly of periodic inorganic and surfactant-based structures has attracted great interest because it extends the range of molecular-sieve materials into the very-large-pore regime. If the synthetic approach can be generalized to transition-metal oxide mesostructures, the resulting nanocomposite materials might find applications in electrochromic or solid-electrolyte devices3,4, as high-surface-area redox catalysts5 and as substrates for biochemical separations. We have proposed recently6 that the matching of charge density at the surfactant/inorganic interfaces governs the assembly process; such co-organization of organic and inorganic phases is thought to be a key aspect of biomineralization7. Here we report a generalized approach to the synthesis of periodic mesophases of metal oxides and cationic or anionic surfactants under a range of pH conditions. We suggest that the assembly process is controlled by electrostatic complementarity between the inorganic ions in solution, the charged surfactant head groups and—when these charges both have the same sign—inorganic counterions. We identify a number of different general strategies for obtaining a variety of ordered composite materials.

Handbook of inorganic electrochromic materials

Abstract: Part 1 Case study on tungsten oxide: bulk crystalline tungsten oxide tungsten oxide films - preparation, structure, and composition of evaporated films tungsten oxide films - preparation, structure, and composition of sputter-deposited films tungsten oxide films - preparation, structure, and composition of electrochemically and chemically prepared films tungsten oxide films - ion intercalation/deintercalation studied by electrochemical techniques tungsten oxide films - ion intercalation/deintercalation studied by physical techniques tungsten oxide films -ultraviolet absorption and semiconductor bandgap tungsten oxide films - optical properties in the luminous and near-infrared range tungsten oxide films - theoretical models for the optical properties tungsten oxide films - electrical properties. Part 2 Electrochromism among the oxides (except tungsten oxide): molybdenum oxide films miscellaneous tungsten- and molybdenum-oxide-containing films iridium oxide films titanium oxide films manganese oxide films vanadium dioxide films vanadium pentoxide films nickel oxide films cobalt oxide films niobium oxide films miscellaneous oxide films systematics for the electrochromism in transition metal oxides inorganic non-oxide electrochromic materials. Part 3 Electrochromic devices: transparent electrical conductors electrolytes and ion conductors ion storage materials - brief overview devices with liquid electrolytes devices with solid inorganic electrolytes and ion conductors devices with polymer electrolytes time-dependent device performance - a unified treatment.

Organic materials for electronic and optoelectronic devices

Abstract: 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.

Transparent conductors as solar energy materials: A panoramic review

Abstract: Transparent conductors (TCs) have a multitude of applications for solar energy utilization and for energy savings, especially in buildings. The largest of these applications, in terms of area, make use of the fact that the TCs have low infrared emittance and hence can be used to improve the thermal properties of modern fenestration. Depending on whether the TCs are reflecting or not in the near infrared pertinent to solar irradiation, the TCs can serve in “solar control” or “low-emittance” windows. Other applications rely on the electrical conductivity of the TCs, which make them useful as current collectors in solar cells and for inserting and extracting electrical charge in electrochromic “smart windows” capable of combining energy efficiency and indoor comfort in buildings. This Review takes a “panoramic” view on TCs and discusses their properties from the perspective of the radiative properties in our ambience. This approach leads naturally to considerations of spectral selectivity , angular selectivity , and temporal variability of TCs, as covered in three subsequent sections. The spectrally selective materials are thin films based on metals (normally gold or titanium nitride) or wide band gap semiconductors with heavy doping (normally based on indium, tin, or zinc). Their applications to energy-efficient windows are covered in detail, experimentally as well as theoretically, and briefer discussions are given applications to solar cells and solar collectors. Photocatalytic properties and super-hydrophilicity are touched upon. Angular selective TCs, for which the angular properties are caused by inclined columnar nanostructures, are then covered. A discussion of TC-like materials with thermochromic and electrochromic properties follows in the final part. Detailed treatments are given for thermochromic materials based on vanadium dioxide and for electrochromic multi-layer structures (incorporating TCs as essential components). The reference list is extensive and aims at giving an easy entrance to the many varied aspects of TCs.

Applications of functionalized transition metal complexes in photonic and optoelectronic devices

Abstract: Transition metal complexes with low lying excited states are finding increasing use as photosensitizers. Major work horses are those derived from polypyridine complexes and metalloporphyrins. The low-lying metal-to-ligand charge transfer (MLCT) and ligand-centered (π–π*) excited states of these complexes are fairly long-lived to participate in electron transfer processes. The emissive nature and high quantum yields allow development of applications. In this paper we review some of the recent applications of these coordination complexes in photochemical systems for the direct conversion and storage of solar energy. Mesoporous membrane type films with large surface area can be prepared from nanosized colloidal semiconductor dispersions. By suitable molecular engineering, the metal complexes can be readily attached to the surface. These films with anchored complexes are finding increasing use in energy conversion devices such as dye-sensitized photoelectrochemical solar cells, intercalation batteries, optical display and optical sensors. Principles of operation of these optoelectronic devices are reviewed here. Various approaches to anchoring molecules on surfaces are first reviewed followed by an overview of the methods of preparation of mesoporous films. This is followed by a comprehensive discussion of the design details of the dye-sensitized solar cells and associated mechanistic studies. Principles of operation of electrochromic and photoelectroluminescent devices based on anchored polypyridine complexes of Ru are also indicated.