CNT-TiO core-shell structure: synthesis and photoelectrochemical characterization.

Porous composite coatings, made of a carbon nanotube (CNT)-TiO core-shell structure, were synthesized by the hybrid CVD-ALD process. The resulting TiO shell features an anatase crystalline structure that covers uniformly the surface of the CNTs. These composite coatings were investigated as photoanodes for the photo-electrochemical (PEC) water splitting reaction.

Conversion-Alloying Anode Materials for Sodium Ion Batteries.

The past decade has witnessed a rapidly growing interest toward sodium ion battery (SIB) for large-scale energy storage in view of the abundance and easy accessibility of sodium resources. Key to addressing the remaining challenges and setbacks and to translate lab science into commercializable products is the development of high-performance anode materials. Anode materials featuring combined conversion and alloying mechanisms are one of the most attractive candidates, due to their high theoretical capacities and relatively low working voltages.

Thermal Conversion of Ethanol into Carbon Nanotube Coatings with Adjusted Packing Density.

The ability to control the growth of carbon nanotube (CNT) coatings with adjusted packing density is essential for the design of functional devices with an emphasized interaction with the surrounding medium. This challenge is addressed in the present study using an innovative single-pot chemical vapor deposition (CVD) process based on the thermal conversion of ethanol to CNTs. Benefitting from the relatively safe and easily bio-derived carbon source is enabled using a cobalt catalyst and a magnesium oxide promoter.

Prussian Blue Analogs for Rechargeable Batteries.

Non-lithium energy storage devices, especially sodium ion batteries, are drawing attention due to insufficient and uneven distribution of lithium resources. Prussian blue and its analogs (Prussian blue analogs [PBAs]), or hexacyanoferrates, are well-known since the 18th century and have been used for hydrogen storage, cancer therapy, biosensing, seawater desalination, and sewage treatment. Owing to their unique features, PBAs are receiving increasing interest in the field of energy storage, such as their high theoretical specific capacity, ease of synthesis, as well as low cost.

Optical and morphological properties of thermochromic VO coatings.

We present optical and morphological characterizations performed on thermochromic VO coatings. VO coatings were obtained by oxidation of as-deposited VOx films. Comparisons were made among coatings oxidized at various temperatures.

Visible Thermochromism in Vanadium Pentoxide Coatings.

Although di-vanadium pentoxide (VO) has been a candidate of extensive research for over half a century, its intrinsic thermochromism has not been reported so far. Films of VO grown on silicon, glass, and metal substrates by metal organic chemical vapor deposition in this study exhibit a thermally induced perceptible color change from bright yellow to deep orange. Temperature-dependent UV-vis spectroscopy and X-ray diffraction allow the correlation between the reversible continuous red shift of the absorption and the anisotropic thermal expansion along the (001) direction, that is, perpendicular to the sheets constituting the layered structure.

Electrical Switching in Semiconductor-Metal Self-Assembled VO Disordered Metamaterial Coatings.

As a strongly correlated metal oxide, VO inspires several highly technological applications. The challenging reliable wafer-scale synthesis of high quality polycrystalline VO coatings is demonstrated on 4" Si taking advantage of the oxidative sintering of chemically vapor deposited VO films. This approach results in films with a semiconductor-metal transition (SMT) quality approaching that of the epitaxial counterpart.

Rational design of functional oxide thin films with embedded magnetic or plasmonic metallic nanoparticles.

Getting into films: semiconductor thin films containing magnetic or plasmonic metal nanoparticles are key materials for the development of high-efficiency solar cells, bright light-emitting diodes, and new magnetoelectric devices. The catalytically driven chemical vapor deposition offers a unique way to combine deposition of the metallic nanoparticles with that of functional oxides to produce such films.

Unusual enhancement in electrical conductivity of tin oxide thin films with zinc doping.

Electrical conductivity of SnO(2)-based oxides is of great importance for their application as transparent conducting oxides (TCO) and gas sensors. In this paper, for the first time, an unusual enhancement in electrical conductivity was observed for SnO(2) films upon zinc doping. Films with Zn/(Zn + Sn) reaching 0.

Tailoring the properties and the reactivity of the spinel cobalt oxide.

Pulsed spray evaporation chemical vapor deposition (PSE-CVD) was employed for the synthesis of cobalt-based spinel oxide thin films, Co(3-x)Fe(x)O4 with x = 0-1.56. XRD, Raman scattering and FTIR emission spectroscopy show that the normal spinel structure was retained for 0 < or = x < or = 0.

Low-temperature thermolysis behavior of tetramethyl- and tetraethyldistibines.

The thermolysis behavior of tetramethyl- and tetraethyldistibine (Sb(2)Me(4) and Sb(2)Et(4)) was investigated using a mass spectrometer coupled to a tubular flow reactor under near-chemical vapor deposition (CVD) conditions. Sb(2)Me(4) undergoes a gas-phase disproportionation with an estimated activation energy of 163 kJ/mol. This reaction leads to the formation of methylstibinidine, SbMe, that reacts on the surface to produce antimony film and SbMe(3).

Mass-spectrometric monitoring of the thermally induced decomposition of trimethylgallium, tris(tert-butyl)gallium, and triethylantimony at low pressure conditions.

The thermal decomposition of trimethylgallium (GaMe(3)), tris(tert-butyl)gallium (Ga(t)Bu(3)) and triethylantimony (SbEt(3)) was investigated in a tubular hot-wall reactor coupled with a molecular-beam sampling mass spectrometer, and decomposition mechanisms were proposed. The obtained results confirm the predominance of the surface reactions and reveal that the radical decomposition path of Ga(t)Bu(3) and SbEt(3), responsible for the formation of butane and ethane respectively, is restricted to a narrow temperature range in contrast to the molecular route that is responsible for the formation of the corresponding alkenes. GaMe(3) decomposes above 480 degrees C, forming essentially methane and also ethane to a lesser extent, whereas Ga(t)Bu(3) decomposes starting 260 degrees C to form predominantly i-butane and i-butene as major species.