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Advanced Superionic Conductors
An advanced superionic conductor (AdSIC) in materials science, is fast ion conductor that has a crystal structure close to optimal for fast ion transport (FIT). History The term was introduced in a paper by A.L. Despotuli, A.V. Andreeva and B. Rambaby. Characteristics The rigid ion sublattice of Advanced SuperIonic Conductors (AdSICs) has structure channels where mobile ions of opposite sign migrate. Their ion-transport characteristics display ionic conductivity of ~0.3/Ω cm ( RbAg4I5, 300 K) and activation energy of Ei~0.1 eV. This determines the temperature-dependent concentration of mobile ions ni~Ni x eEi/kBT capable to migrate in conduction channels at each moment (Ni~1022/cm3, ni~2x1020/cm3, 300 K). The Rubidium silver iodide–family is a group of AdSIC compounds and solid solutions that are isostructural with the RbAg4I5 alpha modification. Examples of such compounds with mobile Ag+- and Cu+-cations include KAg4I5, NH4Ag4I5, K1−xCsxAg4I5, Rb1−xCsxAg4I5, CsAg4Br1 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fast Ion Conductor
In materials science, fast ion conductors are solid conductors with highly mobile ions. These materials are important in the area of solid state ionics, and are also known as solid electrolytes and superionic conductors. These materials are useful in batteries and various sensors. Fast ion conductors are used primarily in solid oxide fuel cells. As solid electrolytes they allow the movement of ions without the need for a liquid or soft membrane separating the electrodes. The phenomenon relies on the hopping of ions through an otherwise rigid crystal structure. Mechanism Fast ion conductors are intermediate in nature between crystalline solids which possess a regular structure with immobile ions, and liquid electrolytes which have no regular structure and fully mobile ions. Solid electrolytes find use in all solid-state supercapacitors, batteries, and fuel cells, and in various kinds of chemical sensors. Classification In solid electrolytes (glasses or crystals), the ionic condu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Crystal Structure
In crystallography, crystal structure is a description of the ordered arrangement of atoms, ions or molecules in a crystal, crystalline material. Ordered structures occur from the intrinsic nature of the constituent particles to form symmetric patterns that repeat along the principal directions of Three-dimensional space (mathematics), three-dimensional space in matter. The smallest group of particles in the material that constitutes this repeating pattern is the unit cell of the structure. The unit cell completely reflects the symmetry and structure of the entire crystal, which is built up by repetitive Translation (geometry), translation of the unit cell along its principal axes. The translation vectors define the nodes of the Bravais lattice. The lengths of the principal axes, or edges, of the unit cell and the angles between them are the lattice constants, also called ''lattice parameters'' or ''cell parameters''. The symmetry properties of the crystal are described by the con ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rubidium Silver Iodide
Rubidium silver iodide is a ternary inorganic compound with the formula RbAg4I5. Its conductivity involves the movement of silver ions within the crystal lattice. It was discovered while searching for chemicals which had the ionic conductivity properties of alpha-phase silver iodide at temperatures below 146 °C for AgI. RbAg4I5 can be formed by melting together or grinding together stoichiometric quantities of rubidium iodide and silver(I) iodide. The reported conductivity is 25 siemens per metre (that is a 1×1×10 mm bar would have a resistance of 400 ohms along the long axis). The crystal structure is composed of sets of iodine tetrahedra; they share faces through which the silver ions diffuse. RbAg4I5 was proposed around 1970 as a solid electrolyte for batteries, and has been used in conjunction with electrodes of silver and of RbI3. Its conductivity does not exhibit substantial variation with changes in relative humidity. Rubidium silver iodide family is a group ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Supercapacitors
A supercapacitor (SC), also called an ultracapacitor, is a high-capacity capacitor, with a capacitance value much higher than other capacitors but with lower voltage limits. It bridges the gap between electrolytic capacitors and Rechargeable battery, rechargeable batteries. It typically stores 10 to 100 times more specific energy, energy per unit volume or mass than electrolytic capacitors, can accept and deliver charge much faster than batteries, and tolerates many more charge and discharge cycles than Rechargeable battery, rechargeable batteries. Supercapacitors are used in applications requiring many rapid charge/discharge cycles, rather than long-term compact energy storage — in automobiles, buses, trains, cranes and elevators, where they are used for Regenerative brake, regenerative braking, short-term energy storage, or burst-mode power delivery. Smaller units are used as power backup for static random-access memory (SRAM). Unlike ordinary capacitors, supercapacito ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nanoionic Supercapacitors
Nanoionics is the study and application of phenomena, properties, effects, methods and mechanisms of processes connected with fast ion transport (FIT) in all-solid-state nanoscale systems. The topics of interest include fundamental properties of oxide ceramics at nanometer length scales, and fast ion conductor ( advanced superionic conductor)/electronic conductor heterostructures. Potential applications are in electrochemical devices (electrical double layer devices) for conversion and storage of energy, charge and information. The term and conception of nanoionics (as a new branch of science) were first introduced by A.L. Despotuli and V.I. Nikolaichik (Institute of Microelectronics Technology and High Purity Materials, Russian Academy of Sciences, Chernogolovka) in January 1992. A multidisciplinary scientific and industrial field of solid state ionics, dealing with ionic transport phenomena in solids, considers Nanoionics as its new division. Nanoionics tries to describe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Deep-sub-voltage Nanoelectronics
Deep-sub-voltage nanoelectronics are integrated circuits (ICs) operating near theoretical limits of energy consumption per unit of processing. These devices are intended to address the needs of applications such as wireless sensor networks which have dramatically different requirements from traditional electronics. For example, for microprocessors where performance is a primary metric of interest, but for some new devices, energy per instruction has become a more sensible metric. The important case of fundamental ultimate limit for logic operation is the reversible computing. The tiny autonomous devices (for example smartdust or autonomous Microelectromechanical systems Microelectromechanical systems (MEMS), also written as micro-electro-mechanical systems (or microelectronic and microelectromechanical systems) and the related micromechatronics and microsystems constitute the technology of microscopic devices, ...) are based on deep-sub-voltage nanoelectronics.http://www.nano ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
