Redox-active organic compounds have been studied as corrosion inhibitors for steel. Even though it is clear that chemical interactions at the organic–metal oxide interface are behind this inhibitive process, detailed mechanism not yet fully understood. Using phenyl-capped aniline tetramer (PCAT), we elucidated with iron oxide. We demonstrate partial reduction of oxidized PCAT and oxidation reduced upon interaction X-ray photoelectron spectroscopy reveals appearance charged nitrogen...

Vinylferrocene was used to grow ordered molecular lines on the H−Si(100) surface via a self-directed growth process. High-resolution STM images reveal zigzag structure within that results from relief of steric crowding molecules. Scanning with more than −4.0 V sample bias reproducibly destroys molecules, leaving smaller decomposition products in their place. The energetics both adsorption and molecules were examined DFT calculations. We propose utilize these metal-containing as prepatterned...

Conductive forms of MoS 2 are important emerging 2D materials due to their unique combination properties such as high electrical conductivity, availability active sites in edge and basal planes for catalytic activity expanded interlayer distances. Consequently, there has been a drive find synthetic routes toward conductive . Naturally occurring or synthetically grown semiconducting 2H-MoS can either be converted into metallic 1T-MoS , various dopants may introduced modulate the electronic...

Current interest in methods for controllably adding organic molecules to silicon surfaces relates proposed hybrid silicon-organic devices. It was recently shown that a "self-directed" growth process, requiring only limited scanned probe intervention, has the potential permit rapid, parallel production of ordered molecular nanostructures on with predefined absolute position, structure, composition, and extent growth. The organic-silicon structures formed are bound by strong covalent...

Testing applications with a graphical user interface (GUI) is an important, though challenging and time consuming task. The state of the art in industry are still capture replay tools, which may simplify recording execution input sequences, but do not support tester finding fault-sensitive test cases leads to huge overhead on maintenance when GUI changes. In earlier works authors presented TESTAR tool, automated approach testing at level whose objective solve part problem by automatically...

Water is fundamental to most aspects of human civilization and terrestrial life in general. The problem deteriorating water quality very real, but often hard quantify for lack data. Hence the development sensors has become an urgently important area research. Here we summarize emerging class based on field effect or chemiresistive geometries, which work completely solid state can operate without reference electrodes. Such devices are candidates continuous online monitoring applications...

Single-wall carbon nanotubes (SWCNTs) are commonly dispersed via sonication in a solvent prior to functionalization. We show that solvents such as dichloromethane, chloroform, 1,2-dichloroethane, and o-dichlorobenzene lead an upward shift the Raman response of SWCNTs. have used model molecule explain this effect, 9 cm(-1) is observed D* band. This blue associated with p-type doping triggered only when sonicated solvent. Sonication decomposes chlorinated solvents, new species (Cl2 HCl(g))...

Free chlorine from dissolved gas is widely used as a disinfectant for drinking water. The residual concentration has to be continuously monitored and accurately controlled in certain range around 0.5–2 mg/l ensure water safety quality. However, simple, reliable, reagent free monitoring devices are currently not available. Here, we present sensor that uses oxidation of phenyl-capped aniline tetramer (PCAT) dope single wall carbon nanotubes (SWCNTs) change their resistance. PCAT by switches...

We show that electropolishing of tantalum metal in a single step about 5 min can reproducibly lead to dimples tens nanometers diameter, regular shape, monodispersed size, and arranged highly ordered arrays which even transverse grain boundaries. Dimpled is ductile, high melting, chemically inert, makes it suitable for nanostructure synthesis under extreme conditions, as demonstrated with simple sputter coating flame annealing procedure gold nanoparticles.

Using the Bingel reaction as a model for side-wall functionalization of single-walled carbon nanotubes, we report discovery highly regular, long-distance (several nanometer) patterns and examine conditions occurrence such patterns, possibly due to long-range induced reactivity. Varying periodicities have been observed via scanning tunneling microscopy are attributed nanotube geometry. Patterns most prominent on medium heavy functionalized nanotubes likely tied nucleophilic mechanism.

Graphene-based pH sensors are a robust, durable, sensitive, and scalable approach for the sensitive detection of in various environments. However, mechanisms through which graphene responds to variations not well-understood yet. This study provides new look into surface science graphene-based address existing gaps inconsistencies among literature concerning sensing response, role defects, surface/solution interactions. Herein, we demonstrate dependence response on defect density level...

Free chlorine is the most commonly used water disinfectant. Measuring its concentration during and after treatment crucial to ensure effectiveness. However, many of existing methods do not allow for continuous on-line monitoring. Here we demonstrate a solid state chemiresistive sensor using graphene-like carbon (GLC) that overcomes issue. GLC films were either bare or non-covalently functionalized with redox-active phenyl-capped aniline tetramer (PCAT) successfully employed quantify aqueous...

A comprehensive study of the oxide formed on GaAs by exposure to ultraviolet light and ozone (UV-ozone), evolution Au nanoparticles UV-ozone treated GaAs(100) substrates, has been carried out using x-ray photoelectron spectroscopy. The found consist oxides gallium arsenic in addition having a significant contribution from elemental concentrated mostly at substrate-oxide interface. An intermediate suboxide species −AsxGa2O is make up substantial part layer, near surface region, whereas...

Nanoscale surface patterning is of great importance for applications ranging from catalysts to biomaterials. We show the formation ordered nanoscale dimple arrays on titanium, tungsten, and zirconium during electropolishing, demonstrating versatility a process previously only reported tantalum. This rare example an electrochemical pattern that can be translated other materials. The dimpled surfaces have been characterized with scanning electron microscopy, transmission atomic force X-ray...

Ultrathin films are important nanoscale structures that used extensively in a variety of technological contexts. However, it has traditionally been difficult and costly to fabricate detachable purely inorganic high aspect ratio with controlled thickness good uniformity. Here we report versatile method make separable membranes various metal oxides such as Nb2O5, TiO2, WO3, Ta2O5 thicknesses ranging from 30 150 nm. Fluoride ions migrated through the oxide film upon arrival at oxide−metal...

To utilize carbon nanotubes in real-world applications, we have to master their chemistry. At present there is a lack of understanding regarding what happens during basic manipulations, such as doping with acids, forming suspensions by sonication water surfactants, or detecting peroxides. We show that leads the situ formation molecular oxygen, causing doping, which can be quenched ethanol. In presence anionic surfactant sodium dodecyl sulfate, oxygen overshadowed due sulfate group. Stable...

High surface area metals are of great importance for applications ranging from catalysts and electrodes to sensors or biomaterials. Many patents scientific papers devoted a range manufacturing approaches commonly involving multistep processing under harsh conditions, lacking general applicability bearing the potential contamination. Here we demonstrate fabrication porous metal layers by anodization at moderate voltages in highly concentrated acids. Porous were produced on copper, silver,...

Colorimetric methods are commonly used to quantify free chlorine in drinking water. However, these not suitable for reagent-free, continuous, and autonomous applications. Here, we demonstrate how functionalization of a pencil-drawn film with phenyl-capped aniline tetramer (PCAT) can be quantitative electric readout concentrations. The functionalized implemented simple fluidic device continuous sensing aqueous sensor is selective undergo reagent-free reset further measurements. Our superior...