Search results for "INTERFACE"

Ionic Liquid-Based Electrolytes for Supercapacitor and Supercapattery

2019

There is a strong desire to replace or complement aqueous and organic electrolytes by ionic liquids (ILs) in electrochemical energy storage (EES) devices to achieve high operating voltages and hence high energy capacity. ILs are regarded as the inherent and competitive electrolytes since they were introduced to the electrochemical research community because they can overcome many disadvantages of the conventional aqueous and organic electrolytes, such as narrow potential windows, volatility, and flammability. This paper reviews critically the recent literatures of IL-based electrolytes used in supercapacitor, supercapattery, and micro-supercapacitor. Supercapattery is a generic term for var…

Effect of alloying elements on the electronic properties of thin passive films formed on carbon steel, ferritic and austenitic stainless steels in a …

2014

The influence of alloying elements on the electrochemical and semiconducting properties of thin passive films formed on several steels (carbon steel, ferritic and austenitic stainless steels) has been studied in a highly concentrated lithium bromide (LiBr) solution at 25 °C, by means of potentiodynamic tests and Mott Schottky analysis. The addition of Cr to carbon steel promoted the formation of a p-type semiconducting region in the passive film. A high Ni contentmodified the electronic behaviour of highly alloyed austenitic stainless steels.Mo did notmodify the electronic structure of the passive films, but reduced the concentration of defects.

Friction and wear testing of multilayer coatings on carbide substrates for dry machining applications

2002

Abstract The principle aim of this paper is to investigate three wear-protective coatings with multilayer structures, which are frequently used in the cutting tool industry and to assess their frictional behaviour under the test conditions equivalent to those for the cutting of medium carbon steel. A modified pin-on-disc tester was used to conduct experiments in which both the friction coefficient and the linear wear of the tribo-pair were recorded vs. sliding distance. The volumetric wear rate was proposed as a parameter for quantitative comparison of the wear resistance of the tribo-pairs tested. It was found that the principle stage of the specimen wear takes place during the first 200–2…

Investigations on friction and wear mechanisms of the PVD-TiAlN coated carbide in dry sliding against steels and cast iron

2006

Abstract The tribological behaviour of the monolayer PVD-titanium aluminium nitride (TiAlN) coated carbide inserts in unidirectional dry sliding against steel and cast iron counterparts was investigated using the pin-on-disc standard test with varying sliding speeds and normal loads. Three different materials of various machinability rates were used as the counterparts, namely the normalised medium carbon steel C45 equivalent to AISI 1045, austenitic stainless steel 1H18N9T equivalent to AISI 304 and gray cast iron EN-GJL-300 with flake-shaped graphite. A pin-on-disc device with round tool inserts was used to conduct friction and wear tests in which both the friction coefficient and the lin…

Atomic layer deposition of Ti-Nb-O thin films onto electrospun fibers for fibrous and tubular catalyst support structures

2018

Here, the authors report on the preparation of core-shell carbon-ceramic fibrous as well as ceramic tubular catalyst supports utilizing electrospinning and atomic layer deposition (ALD). In this paper, ALD of Ti-Nb-O thin films using TiCl4, Nb(OEt)5, and H2O as precursors is demonstrated. According to the time-of-flight-elastic recoil detection analysis and Rutherford backscattering spectrometry, carbon and hydrogen impurities were relatively low, but depend on the pulsing ratio of the precursors. Optimized ALD process was used for coating of sacrificial electrospun polyvinyl alcohol (PVA) template fibers to yield tubular Ti-Nb-O structures after thermal or solution based PVA removal. Anoth…

Soluble IF-ReS2 nanoparticles by surface functionalization with terpyridine ligands.

2010

A major drawback in the application of layered chalcogenide nanoparticles/tubes is their inertness to chemical and biological modification and functionalization. Their potential use in composite materials might be greatly enhanced by improving the chalcogenide/matrix interface bonding. A novel modification strategy for layered chalcogenide nanoparticles based on the chalcophilic affinity of metals and the chelating terpyridine is reported. The terpyridine anchor group can be conjugated to fluorescent tags or hydrophilic/hydrophobic groups that confer solubility in various solvents to the otherwise insoluble chalcogenide nanoparticles. The functionalized particles are characterized using TEM…

Thickness identification of atomically thin InSe nanoflakes on SiO2/Si substrates by optical contrast analysis

2015

Abstract Single layers of chalcogenide semiconductors have demonstrated to exhibit tunable properties that can be exploited for new field-effect transistors and photonic devices. Among these semiconductors, indium selenide (InSe) is attractive for applications due to its direct bandgap in the near infrared, controllable p- and n-type doping and high chemical stability. For its fundamental study and the development of practical applications, rapid and accurate identification methods of atomically thin nanosheets are essential. Here, we employ a transfer matrix approach to numerically calculate the optical contrast between thin InSe flakes and commonly used SiO2/Si substrates, which nicely re…

Reverse Micelle Synthesis and Characterization of ZnSe Nanoparticles

2000

The phase composition of the passive layer on iron

1988

Effective interactions of colloids on nematic films.

2008

The elastic and capillary interactions between a pair of colloidal particles trapped on top of a nematic film are studied theoretically for large separations $d$. The elastic interaction is repulsive and of quadrupolar type, varying as $d^{-5}$. For macroscopically thick films, the capillary interaction is likewise repulsive and proportional to $d^{-5}$ as a consequence of mechanical isolation of the system comprised of the colloids and the interface. A finite film thickness introduces a nonvanishing force on the system (exerted by the substrate supporting the film) leading to logarithmically varying capillary attractions. However, their strength turns out to be too small to be of importanc…