There is, I think, something ethereal about i —the square root of minus one. I remember first hearing about it at school. It seemed an odd beast at that time—an intruder hovering on the edge of reality.

Usually familiarity dulls this sense of the bizarre, but in the case of i it was the reverse: over the years the sense of its surreal nature intensified. It seemed that it was impossible to write mathematics that described the real world in …

I and i

Solid-state electrolytes are attracting increasing interest for electrochemical energy storage technologies. In this Review, we provide a background overview and discuss the state of the art, ion-transport mechanisms and fundamental properties of solid-state electrolyte materials of interest for energy storage applications. We focus on recent advances in various classes of battery chemistries and systems that are enabled by solid electrolytes, including all-solid-state lithium-ion batteries and emerging solid-electrolyte lithium batteries that feature cathodes with liquid or gaseous active materials (for example, lithium–air, lithium–sulfur and lithium–bromine systems). A low-cost, safe, aqueous electrochemical energy storage concept with a ‘mediator-ion’ solid electrolyte is also discussed. Advanced battery systems based on solid electrolytes would revitalize the rechargeable battery field because of their safety, excellent stability, long cycle lives and low cost. However, great effort will be needed to implement solid-electrolyte batteries as viable energy storage systems. In this context, we discuss the main issues that must be addressed, such as achieving acceptable ionic conductivity, electrochemical stability and mechanical properties of the solid electrolytes, as well as a compatible electrolyte/electrode interface. This Review details recent advances in battery chemistries and systems enabled by solid electrolytes, including all-solid-state lithium-ion, lithium–air, lithium–sulfur and lithium–bromine batteries, as well as an aqueous battery concept with a mediator-ion solid electrolyte.

Lithium battery chemistries enabled by solid-state electrolytes

The science and technology of ultracapacitors are reviewed for a number of electrode materials, including carbon, mixed metal oxides, and conducting polymers. More work has been done using microporous carbons than with the other materials and most of the commercially available devices use carbon electrodes and an organic electrolytes. The energy density of these devices is 3¯5 Wh/kg with a power density of 300¯500 W/kg for high efficiency (90¯95%) charge/discharges. Projections of future developments using carbon indicate that energy densities of 10 Wh/kg or higher are likely with power densities of 1¯2 kW/kg. A key problem in the fabrication of these advanced devices is the bonding of the thin electrodes to a current collector such the contact resistance is less than 0.1 cm2. Special attention is given in the paper to comparing the power density characteristics of ultracapacitors and batteries. The comparisons should be made at the same charge/discharge efficiency.

Ultracapacitors: Why, How, and Where is the Technology

羟氨苄青霉素引起大疱性类天疱疮样疹

Note: Times Cited: 875 Reference EPFL-ARTICLE-206025doi:10.1021/cr0501846View record in Web of Science URL: ://WOS:000249839900009 Record created on 2015-03-03, modified on 2017-05-12

Complex Hydrides for Hydrogen Storage

https://iopscience.iop.org/article/10.1088/1674-1056/28/6/067304/pdf

Method of evaluating interface traps in Al 2 O 3 /AlGaN/GaN high electron mobility transistors

In this work, the formation and evolution mechanism of nanocavities generated on the surface of TiO2 nanofibers during the phase transformation were investigated through ex situ and in situ transmission electron microscopy and X-ray diffraction. The results indicate that the calcination atmosphere plays an important role in the morphology of the nanocavities. For the TiO2 nanofibers calcined in air, the nanocavities show a hexagonal prism morphology, which is related to the phase transformation from TiO2 (B) to anatase. Meanwhile, under vacuum conditions, the nanocavities exhibit an irregular shape due to the occurrence of phase transition from TiO2 (B) to Ti3O5. The difference in the morphologies of these nanocavities leads to the different surface areas of the nanofibers and further affects the photocatalytic activity. This work also illustrates that the phase transformation from anatase to rutile is not only related to the activation temperature, but also to the calcination atmosphere. Ultra-high vacuum may retard the transformation.

In situ observation and investigation on the formation mechanism of nanocavities in TiO2 nanofibers

Gel Polymer Electrolyte with Anion‐Trapping Boron Moieties via One‐Step Synthesis for Symmetrical Supercapacitors

New view on the variation of forward conduction mechanisms derived from electrical stress in UV-A light emitting diodes

The reliability of traditional T-gate AlGaN/GaN high electron mobility transistor (HEMT) fabricated by the low power fluorine plasma treatment was investigated by applying the off-state high electric field stress The new electrical degradation phenomenon of AlGaN/GaN HEMT with low power fluorine plasma treatment is discovered The electrical parameters show a rapid degradation in a short time, and then keeping mostly unchangeable The migration phenomenon of fluorine ions is further validated by the electron redistribution and breakdown voltage enhancement after off-state stress Due to fluorine's strong electronegativity, the migration of fluorine can induce build-in electric field Thereby, it would prevent the drift of the subsequent fluorine ions and alleviate further degradation of AlGaN/GaN HEMT

Xiaohua Ma

Papers

Method of evaluating interface traps in Al 2 O 3 /AlGaN/GaN high electron mobility transistors

In situ observation and investigation on the formation mechanism of nanocavities in TiO2 nanofibers

Gel Polymer Electrolyte with Anion‐Trapping Boron Moieties via One‐Step Synthesis for Symmetrical Supercapacitors

New view on the variation of forward conduction mechanisms derived from electrical stress in UV-A light emitting diodes

Influence of the built-in electric field induced bby low power fluorine plasma implantation on the reliability of AlGaN-GaNHEMTs