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BN nanosheets-coated SrAl2O4:Eu2+ was fabricated by a simple one-pot method. The BN nanosheets formed into a compact layer coating on the surface of SrAl2O4:Eu2+ completely. X-ray diffraction, X-ray photoelectron spectroscopy and various microscopy techniques were used to analysis the composite structure of the phosphor. BN layer obstructed H2O molecule entering into the channels of SrAl2O4, and restrain SrAl2O4 from hydrolyzing effectively. The coated phosphor shows a strong green band at about 510 nm which corresponds to the 4f7–4f65d transition in Eu2+ ion.

In this paper we report on the synthetic investigation of single-crystalline aluminum borate (Al 4 B 2 O 9 ) nanowires in large scale by a direct calcination of a precursor powder made of Na 2 B 4 O 7 ·10H 2 O and Al (NO 3 ) 3 ·9H 2 O at a low temperature of 850 °C. The nanowires, with the diameter of 20–40 nm and the length up to several micrometers, possess smooth surfaces and uniform sizes along the entire wire. The growth mechanism of the nanowires is attributed to a solid–liquid–solid process, which controls the nanowire morphology.

Based on a methanol-thermal reaction method, coating carbon nanotubes (CNTs) with needle-like iron oxide has been achieved. The structure, composition and morphology of the coatings were characterized by using transmission electron microscopy, X-ray energy dispersive spectrum and X-ray photoelectron spectroscopy. The experimental results indicate that the pre-oxidation of CNTs and the acid-based methanol-thermal environment are very important points to obtain dense and uniform coatings on CNTs. Magnetic measurement for the iron oxide coatings indicates that the coercivity has been enhanced after coating.

Multilayer nanowire webs of aluminum borate (Al18B4O33) have been synthesized by a solid-state reaction of boron, boron oxide, and aluminum oxide at high temperature without using any template or substrate. Alumina powder on a micron scale provides an in-situ reaction container resulting in self-oriented growth of the aluminum borate nanowires. The orientation could be maintained by a quenching treatment. The addition of boron should be responsible for the generation of the web morphology. Without any further purification, a large amount of nanowire webs with high purity was obtained. Further experiments were carried out to investigate the morphological dependence on the reactant compositions. The possible growth mechanism for the nanowebs was detailed based on extensive analysis and examination.

A facile method was proposed to directly synthesize the completely coated aluminum borate (Al18B4O33) nanowire webs with BN by an epitaxial growth process. The BN-Al18B4O33 nanocable webs could be obtained by the reaction of Al18B4O33 nanowire webs, B2O3, and ammonia at 1200 degrees C. The high-temperature stable Al18B4O33 nanowire webs acted as a template for the epitaxial coating of BN. The coating was characterized by the means of X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), and infrared spectrum (IR). High-resolution transmission electron microscopy (HRTEM) clearly shows the BN coating layers closely attached to the inner nanowires. The typical thickness of the BN shells is similar to 5 nm. The growth mechanism of the present BN-coated aluminum borate (Al18B4O33) nanostructures was also proposed.

Large-area and fast production of single-crystal Al 4 B 2 O 9 nanorods is reported via simple thermal chemical route by the reaction of B with B 2 O 3 and Al 2 O 3 in 1050 °C air atmosphere. There is no other metal catalyst and protective carrier gas in the process. We can also obtain Al 18 B 4 O 33 nanorods by annealing above obtained Al 4 B 2 O 9 nanorods which included a little alumina. The scanning electron microscope measurements showed that the aluminum borate nanorods obtained had uniform diameters in the range of 30 to 50 nm and the lengths up to about 1 μm. The duration time influence on the products was also investigated.

A simple method based on a hydrothermal process using alkali salts as mineralizers is proposed for the synthesis of aligned bunches of boehmite (gamma-AlOOH) nanowires without a template's assistance. Most bunches of aligned boehmite nanowires are constructed by two separated shorter bundles with widths of 700 to approximately 800 nm and lengths of about 1 microm. XRD patterns, FTIR spectra, and SEM and TEM images were used to characterize the products. The specific surface area and pore-size distribution of the obtained product as determined by gas-sorption measurements show that the boehmite bundles possess a high BET surface area and porosity properties. The importance of adding Na2B4O7 salts for the formation of bundle morphologies has been discussed.

High-aspect-ratio and single-crystal aluminum borate (Al18B4O33) nanowire bundles with an ordered orientation were synthesized by using an innovative sucrose-assisted growth process. The process involves the dehydration and polycondensation of aluminum borate−sucrose solution to form a highly viscous precursor. The sucrose plays a crucial role in the growth of the nanowire bundles by supporting as a polymeric substrate and a type of adhesive template. Electron microscopy was used to characterize the high-aspect-ratio nanowire bundles. A possible growth mechanism for the nanowire bundles is proposed.

Single-crystal and uniform aluminum borate (Al4B2O9)-coited aluminum oxide nanowires have been synthesized in high purity and in large yield via a reaction or metal aluminum with boron oxide in the presence of carbon nanotubes (CNTs). The aluminum oxide nanowires exhibit a well-crystallized one-dimensional structure with diameters ranging front 50 to 70 nm, and the Al4B2O9 have a coating thickness of about 1 5nm. CNTs play a crucial role in the formation of the important ceramic nanowires, by providing a platform to grow the composite structure. The growth mechanism was proposed by the detailed microscopy observations. (c) 2005 Elsevier Inc. All rights reserved.

A simple and fast, controllable gas vaporization of alloy method for producing various micro- and nanostructures of ZnO in air atmosphere with a large yield was presented in this paper. The presence of Cu was proved to strongly affect the growth morphology of the synthesized ZnO through the control of the partial pressure of zinc, which could be fulfilled by changing the composition of Zn and Cu for the used reactants. Given the simplicity of the procedure, and the economic advantages, the method described here is likely to be of interest in industrial-scale applications.

Single-crystal aluminum borate nanowires (Al 18 B 4 O 33 ) with uniform diameter distribution were synthesized by a chemical reaction of alumina with boron monoxide in the presence of a support catalyst. Three comparative experiments were carried out and demonstrated the detailed crystal growth process of the nanowires. We found that two factors, the isolated reaction area with nanometer scale and abundant local reactants at an appropriate reaction temperature, play important roles in determining the diameter, length and yield of the nanowires. The growth mechanism was also prepared.

Gallium borate nanowires have been synthesized using a simple and readily scaleable solid-state reaction among boron, boron oxide and gallium oxide. The GaBO 3 nanowires have diameters ranging from 90 to 150 nm and lengths of several hundreds nanometer, exhibiting a poor crystallization. After a nanoscale support catalyst Fe 2 O 3 /Al 2 O 3 was used as additive in the reaction, the diameters, lengths and crystallization were effectively improved. The nanowires exhibit a well-crystallized one-dimensional single-crystal structure with diameters ranging from 20 to 60 nm and lengths up to several micrometers. The growth mechanism was also presented in this letter.

Nanobamboo and nanotube structures of BN have been controllably synthesized by reaction of barium metaborate with ammonia. The gallium addition plays an important role in the formation of nanotubes. The experimental results indicate that, without the gallium additive, the reaction results in the growth of nanobamboo structure. Gallium addition, probably as a catalyst within the framework of vapor–liquid–solid growth, promotes the growth of nanotubes. High-solution transmission electron microscopy research indicates that rhombohedral stacking order is the dominant atomic arrangement for BN nanobamboos; whereas hexagonal stacking is the dominant arrangement for BN nanotubes.

Single-crystal aluminum borate nanowires (Al 18 B 4 O 33 ) with uniform diameter distribution were synthesized in a large scale by a catalytic growth method. The nanowires exhibit a well-crystallized one-dimensional structure with diameters ranging from 20 to 60 nm. Chemical composition and transmission electron microscopy (TEM) were used to analyze the crystal structure. The growth mechanism was also proposed for the synthesis of Al 18 B 4 O 33 nanowires.

A simple method for synthesizing titanium carbide (TiC) nanowires is demonstrated. TiC nanowires with a covered layer of graphite can be synthesized by the reaction of TiO gas with methane in the presence of a catalyst containing Fe. This graphite layer can be effectively removed by heating as-synthesized samples to 600°C in air. The length of TiC nanowires is several hundreds of microns and their diameters range from 30 to 100 nm. A growth mechanism of TiC nanowires involves vapor–liquid–solid reaction.

A novel method was demonstrated to fabricate boron nitride nanotube films on silicon substrate in a location-controlled fashion. The pre-deposited SiO2 layer on the substrate controls the growth space of BN nanotubes synthesized by an ammonothermal reaction of boron and its oxide.

In this work, we demonstrated the EG-assisted solvothermal synthesis of 3-D microspherical BiOBr architectures assembled by nanosheets. The morphology and compositional characteristics of the 3-D architectures were investigated by various microscopy techniques. The possible formation mechanism for the architectures was discussed. The band gap of the obtained BiOBr materials was estimated to be 2.54 eV by UV–vis. The specific surface area and porosity of the BiOBr 3-D architectures also were investigated by using nitrogen adsorption and desorption isotherms. Because of the narrow bandgap and the novel 3-D micro-/nanostructure, the BiOBr architectures show a more excellent photocatalytic activity under visible light irradiation than the BiOBr bulk plates. Several possible reasons for the higher photocatalytic activity have been taken into consideration. In addition, the photocatalyst is stable during the reaction and can be used repeatedly.

In this work, a hydrothermal route using an ethanol-water solution to progressively synthesize a sequence of flowerlike three-dimensional gamma-AlOOH boehmite nanostructures without employing templates or matrixes for self-assembly is presented. The flowerlike boehmite nanoarchitectures exhibit three hierarchies of self-organization, i.e., single-crystalline nanorods, nanostrips, and bundles, which are characterized by scanning and transmission electron microscopy. The sequence of products obtained after different processing times indicates a self-assembly mechanism. The hydrogen bonding on the surface of nanorods or nanostrips possibly plays a key role, as identified by FTIR spectra of the products after they had been heated to 1000 degrees C. The specific surface area and pore-size distribution of the obtained product as determined by gas-sorption measurements show that the boehmite nanoarchitectures exhibit high BET surface area and porosity properties.