Structure and nanostructure in ionic liquids.

An object is to provide a semiconductor device of which a manufacturing process is not complicated and by which cost can be suppressed, by forming a thin film transistor using an oxide semiconductor film typified by zinc oxide, and a manufacturing method thereof. For the semiconductor device, a gate electrode is formed over a substrate; a gate insulating film is formed covering the gate electrode; an oxide semiconductor film is formed over the gate insulating film; and a first conductive film and a second conductive film are formed over the oxide semiconductor film. The oxide semiconductor film has at least a crystallized region in a channel region.

Semiconductor device, and manufacturing method thereof

Lithium-sulfur (Li-S) batteries have attracted tremendous interest because of their high theoretical energy density and cost effectiveness. The target of Li-S battery research is to produce batteries with a high useful energy density that at least outperforms state-of-the-art lithium-ion batteries. However, due to an intrinsic gap between fundamental research and practical applications, the outstanding electrochemical results obtained in most Li-S battery studies indeed correspond to low useful energy densities and are not really suitable for practical requirements. The Li-S battery is a complex device and its useful energy density is determined by a number of design parameters, most of which are often ignored, leading to the failure to meet commercial requirements. The purpose of this review is to discuss how to pave the way for reliable Li-S batteries. First, the current research status of Li-S batteries is briefly reviewed based on statistical information obtained from literature. This includes an analysis of how the various parameters influence the useful energy density and a summary of existing problems in the current Li-S battery research. Possible solutions and some concerns regarding the construction of reliable Li-S batteries are comprehensively discussed. Finally, insights are offered on the future directions and prospects in Li-S battery field.

More Reliable Lithium-Sulfur Batteries: Status, Solutions and Prospects.

Lithium-sulfur (Li-S) batteries with high energy density and long cycle life are considered to be one of the most promising next-generation energy-storage systems beyond routine lithium-ion batteries. Various approaches have been proposed to break down technical barriers in Li-S battery systems. The use of nanostructured metal oxides and sulfides for high sulfur utilization and long life span of Li-S batteries is reviewed here. The relationships between the intrinsic properties of metal oxide/sulfide hosts and electrochemical performances of Li-S batteries are discussed. Nanostructured metal oxides/sulfides hosts used in solid sulfur cathodes, separators/interlayers, lithium-metal-anode protection, and lithium polysulfides batteries are discussed respectively. Prospects for the future developments of Li-S batteries with nanostructured metal oxides/sulfides are also discussed.

Nanostructured Metal Oxides and Sulfides for Lithium-Sulfur Batteries

Lithium (Li) metal has been considered as an important substitute for the graphite anode to further boost the energy density of Li-ion batteries. However, Li dendrite growth during Li plating/stripping causes safety concern and poor lifespan of Li metal batteries (LMB). Herein, fluoroethylene carbonate (FEC) additives are used to form a LiF-rich solid electrolyte interphase (SEI). The FEC-induced SEI layer is compact and stable, and thus beneficial to obtain a uniform morphology of Li deposits. This uniform and dendrite-free morphology renders a significantly improved Coulombic efficiency of 98% within 100 cycles in a Li | Cu half-cell. When the FEC-protected Li metal anode matches a high-loading LiNi0.5Co0.2Mn0.3O2 (NMC) cathode (12 mg cm−2), a high initial capacity of 154 mAh g−1 (1.9 mAh cm−2) at 180.0 mA g−1 is obtained. This LMB with conversion-type Li metal anode and intercalation-type NMC cathode affords an emerging energy storage system to probe the energy chemistry of Li metal protection and demonstrates the material engineering of batteries with very high energy density.

Fluoroethylene Carbonate Additives to Render Uniform Li Deposits in Lithium Metal Batteries

Aminosilane precursors for depositing silicon-containing films, and methods for depositing silicon-containing films from these aminosilane precursors, are described herein. In one embodiment, there is provided an aminosilane precursor for depositing silicon-containing film comprising the following formula (I):
 
(R 1 R 2 N) n SiR 3 4-n   (I)
 
wherein substituents R 1 and R 2 are each independently chosen from an alkyl group comprising from 1 to 20 carbon atoms and an aryl group comprising from 6 to 30 carbon atoms, at least one of substituents R 1 and R 2 comprises at least one electron withdrawing substituent chosen from F, Cl, Br, I, CN, NO 2 , PO(OR) 2 , OR, SO, SO 2 , SO 2 R and wherein R in the at least one electron withdrawing substituent is chosen from an alkyl group or an aryl group, R 3 is chosen from H, an alkyl group, or an aryl group, and n is a number ranging from 1 to 4.

Precursors for depositing silicon-containing films and methods for making and using same

We present a simple cluster model to understand the dissociative chemisorption of molecular hydrogen and the desorption of atomic hydrogen on platinum small clusters using the gradient-corrected de...

On the Sequential Hydrogen Dissociative Chemisorption on Small Platinum Clusters: A Density Functional Theory Study

A novel magnetic imprinting nanotechnology for selective capture of Gd(3+) from a mixed solution of rare earth ions was developed by simply adding Gd(3+)-imprinted chitosan/carbon nanotube nanocomposite (IIP-CS/CNT) and silica-coated magnetite nanoparticle (SiO2@Fe3O4). The IIP-CS/CNT was prepared for the first time via a facile "surface deposition-crosslinking" method, exhibiting a well-defined coating structure. Interestingly, the neighboring IIP-CS/CNT monomers were held together as bundles, like a network, containing abundant interstitial spaces. When IIP-CS/CNT and SiO2@Fe3O4 were dispersed in a mixed solution of rare earth ions, the magnetic SiO2@Fe3O4 submicrospheres would be trapped in or adhere to the IIP-CS/CNT network, leading to the magnetization of IIP-CS/CNT; meanwhile, Gd(3+) ions could be selectively captured by the magnetized IIP-CS/CNT. Saturation adsorption capacity for Gd(3+) was up to 88 mg g(-1) at 303.15 K, which is significantly higher than the Gd(3+) adsorption capacities for the reported rare earth ion-imprinted adsorbents over recent years. The selectivity coefficients relative to La(3+) and Ce(3+) were 3.50 and 2.23, respectively, which are very similar to those found for other reported CS-based imprinted materials. Moreover, the imprinted adsorbents could be easily and rapidly retrieved by an external magnetic field without the need of additional centrifugation or filtration, greatly facilitating the separation process. Test of reusability demonstrated that the magnetized IIP-CS/CNT could be repeatedly used without any significant loss in binding capacity. Overall, this work not only provides new insights into the fabrication of magnetic imprinted CS-based composite, but also highlights its application for selective adsorption toward rare earth ions.

Selective Adsorption of Gd3+ on a Magnetically Retrievable Imprinted Chitosan/Carbon Nanotube Composite with High Capacity

A new strategy to retrieve chitosan-decorated carbon nanotube (CS/CNT) from aqueous dispersion was proposed. The CS/CNT, prepared via a “surface deposition–crosslinking” method, exhibited an aggregation microstructure with plentiful interstitial spaces. By introducing magnetic nanoparticle (MNP) into CS/CNT dispersion solution, MNP was embedded in the CS/CNT aggregates, which endowed the CS/CNT with magnetic retrievability. Using this strategy, a simple and convenient operation for the removal of anionic azo dye (acid red 18 (AR18)) was achieved by directly adding CS/CNT and MNP into the dye solution, where CS/CNT acted as an adsorbent and MNP enabled all CS/CNT aggregates to be magnetically retrievable. Effects of pH, ionic strength, contact time, temperature, and initial AR18 concentration on adsorption efficiency were investigated. Results showed that AR18 adsorption could achieve equilibrium quickly and the maximum adsorption capacity could be up to 809.9 mg·g–1 at 323.15 K. Full kinetic and thermodyn...

Highly efficient removal of acid red 18 from aqueous solution by magnetically retrievable chitosan/carbon nanotube: Batch study, isotherms, kinetics, and thermodynamics

Chenggang Zhou

Papers

Precursors for depositing silicon-containing films and methods for making and using same

On the Sequential Hydrogen Dissociative Chemisorption on Small Platinum Clusters: A Density Functional Theory Study

Selective Adsorption of Gd3+ on a Magnetically Retrievable Imprinted Chitosan/Carbon Nanotube Composite with High Capacity

Highly efficient removal of acid red 18 from aqueous solution by magnetically retrievable chitosan/carbon nanotube: Batch study, isotherms, kinetics, and thermodynamics

Facile and controllable synthesis of N/P co-doped graphene for high-performance supercapacitors