Synthesis of Pt-Loaded YWO:Eu Microspheres and Their Hydrogen-Sensitive Turn-Off Luminescence.

Pt nanoparticles were loaded on YWO:Eu phosphor microspheres to enhance hydrogen sensitivity at low temperatures through turn-off luminescence. Mesoporous YWO:Eu microspheres were synthesized first by a hydrothermal method. Pt loading on the surface of the YWO:Eu microspheres was then carried out by a method of the self-regulated reduction of surfactants using aqueous KPtCl solutions.

Biphasic Sol-Gel Synthesis of Microstructured/Nanostructured YVO:Eu Materials and Their HO Sensing Ability.

Microstructured/nanostructured YVO:Eu powders and films were synthesized through a biphasic sol-gel method, aiming at their application as HO sensing materials based on the turn-off luminescence of Eu ions. The synthesis was typically carried out at temperatures of 80 °C or lower by using organic solutions to dissolve vanadium alkoxide and aqueous solutions to dissolve yttrium and europium salts together with sodium carboxylates. The resultant crystalline YVO:Eu powders and films were characterized as containing micrometer-sized particles comprising primary nanoparticles with high specific surface areas.

Liquid-Phase Synthesis of Ba2V2O7 Phosphor Powders and Films Using Immiscible Biphasic Organic-Aqueous Systems.

A liquid-phase synthesis of inorganic phosphor materials at a moderate temperature was proposed by using immiscible liquid-liquid biphasic systems. A self-activated Ba2V2O7 phosphor was actually synthesized from vanadium alkoxide dissolved in an organic solution and barium acetate in an aqueous solution. A mild hydrolysis reaction of the alkoxide started at the organic-inorganic interface, and an intermediate compound, Ba(VO3)2·H2O, was initially formed.

Fabrication of porous cubic architecture of ZnO using Zn-terephthalate MOFs with characteristic microstructures.

A method for synthesizing porous cubic-shaped ZnO particles a few tens of micrometers in size is described on the basis of a pyrolytic conversion of Zn-terephthalate metal-organic frameworks (MOFs). MOF crystals were initially grown in solutions containing Zn(NO3)2·6H2O and terephthalic acid as solutes and N,N-dimethylformamide (DMF) or N,N-diethylformamide (DEF) as a solvent under a solvothermal condition. It was the key to controlling the microstructure of MOF cuboids for their use as an intermediate compound for ZnO.

Synthesis of New RE Doped LiTaTiO₃ (RE: Eu, Sm, Er, Tm, and Dy) Phosphors with Various Emission Colors.

New phosphors with various emission colors for RE doped LiTaTiO₃ (LTT) (RE: Eu, Sm, Er, Tm, and Dy) were synthesized by electric furnace at 1423 K for 15 h. The microstructure of the host material and the photoluminescence (PL) property were determined and compared to those of RE doped LiNbTiO₃ (LNT) In the LTT phosphor, the highest PL intensity was achieved for the mixture composition LiTaTiO₃ with a LiTaO₃ structure, although it has an M-phase superstructure. In the LTT host material, the effective activators were Eu and Sm ions, in contrast to the LNT host material.

Liquid-liquid biphasic synthesis of layered zinc hydroxides intercalated with long-chain carboxylate ions and their conversion into ZnO nanostructures.

A method for synthesizing layered zinc hydroxide compounds in high yields is developed using an immiscible liquid-liquid system in one pot. Long-chain carboxylate ions such as heptanoate, decanoate, and dodecanoate were successfully intercalated between zinc hydroxide layers in one process starting from a xylene-water system. Typically, a xylene phase dissolving the respective carboxylic acids was allowed to stand in contact with an aqueous phase dissolving zinc nitrate hexahydrate and urea.

Luminescent antireflective coatings with disordered surface nanostructures fabricated by liquid processes.

Antireflective phosphor coatings having disordered surface nanostructures were fabricated by a sol-gel dip coating method and a subsequent hot water treatment. Thin films of a Bi(3+),Eu(3+)-codoped YVO4 red phosphor were first prepared and effects of the addition of an aluminum source to precursor solutions on their microstructure and optical properties were examined. Optical transmittance of the YVO4:Bi(3+),Eu(3+) film was lower than that of a bare quartz glass substrate due to a higher refractive index of YVO4.

Synthesis of inorganic-organic layered compounds using immiscible liquid-liquid systems under the distribution law.

A method for synthesizing inorganic-organic layered compounds is proposed using a biphasic liquid-liquid system in one pot. Layered basic zinc benzoate (LBZB) compounds were chosen, and their formation was investigated starting from a xylene-water system. In a typical synthesis, a xylene phase dissolving benzoic acid was allowed to stand in contact with an equal amount of an aqueous phase dissolving zinc nitrate hexahydrate and urea.

One-step synthesis of nano-micro chestnut TiO2 with rutile nanopins on the microanatase octahedron.

The solution synthesis of large single crystals of octahedron-like anatase TiO2 is reported, although this novel result is unexpected in the light of reported theoretical calculations. Moreover, systematic control of the crystal growth of rutile nanopins on the microanatase octahedron single crystal results in a nano-micro chestnut-like TiO2 structure. The control of the formation of rutile nanopins on the large single crystals of anatase in the same solution is an interesting and useful technique, based on thermodynamics and surface chemistry.

Layered single-metal hydroxide/ethylene glycol as a new class of hybrid material.

Neutral ethylene glycol (EG) molecules have been intercalated into zinc hydroxide layers to produce a new hybrid material in which only one kind of metal ion is included. Initially, layered basic zinc acetate (LBZA, Zn(5)(OH)(8)(CH(3)COO)(2).2H(2)O) was prepared from a methanolic zinc acetate dihydrate solution.

Superhydrophobic perpendicular nanopin film by the bottom-up process.

We first fabricated the superhydrophobic film with a water contact angle of 178 degrees based on a perpendicular nanopin fractal structure by a bottom-up process. Until now, only materials with an original water contact angle larger than 90 degrees , which is classified as hydrophobicity, could be used to fabricate the superhydrophobic film (>170 degrees ) according to the possible fractal structure by a top-down process. Now, in this work, a water contact angle of about 178 degrees can be achieved using a lauric acid-coated film with an original contact angle of 75 degrees , which is classified as hydrophilicity, based on an ideal fractal structure for the superhydrophobic surface which is fabricated by the nanosize pin with 6.

Fabrication of highly porous and micropatterned SnO2 films by oxygen bubbles generated on the anode electrode.

The fabrication process of highly porous SnO(2) thick film by reaction between tin ions and oxygen gas generated by an anodic applied potential on substrates in SnCl(2) aqueous solution is reported; moreover, we succeeded in forming porous SnO(2) micropatterns through site-selective deposition on a Pt-patterned F-doped SnO(2)(FTO) coated substrate .

Fabrication of nanoparticulate porous LaOF films through film growth and thermal decomposition of ion-modified lanthanum diacetate hydroxide.

This paper first reports fabrication of macro/nanotextured rare-earth oxyfluoride films. Usage of ion-modified lanthanum diacetate hydroxide (LDAH) as self-templates was successful in producing nanoparticulate lanthanum oxyfluoride (LaOF) films. LDAH template films were deposited on glass substrates through a chemical bath deposition in solutions composed of lanthanum acetate sesquihydrate, methanol, trifluoroacetic acid, and aqueous ammonia.

Fabrication and photoluminescence of chemically stable La2O3:Eu3+-La2Sn2O7 core-shell-structured nanoparticles.

Core-shell-structured La2O3:Eu3+-La2Sn2O7 nanoparticles were fabricated through SnO2-coating of LaOF:Eu3+ in an aqueous solution and subsequent heat treatments at a higher temperature. The nanoparticles exhibited high chemical stability under an ambient atmosphere and intense red photoluminescence upon irradiation with ultraviolet light.

Hydrothermal routes to prepare nanocrystalline mesoporous SnO2 having high thermal stability.

We report simple hydrothermal routes to prepare thermally stable SnO2 particles having high specific surface areas and mesoporosity. The preparation method includes a new combination of synthetic processes: hydrolysis of tin(IV) chloride at 95 degrees C in the absence of alkaline solutions (aqueous NH3 or NaOH), formation of nanocrystalline SnO2, and subsequent hydrothermal treatments at temperatures between 100 and 200 degrees C. After annealing treatments of the hydrothermally treated SnO2 particles at 400 or 500 degrees C, their crystallite sizes remained smaller than 7.

Growth of submicrometer-scale rectangular parallelepiped rutile TiO2 films in aqueous TiCl3 solutions under hydrothermal conditions.

Evolution of a new morphology of rutile TiO2 films consisting of nearly single-crystalline parallelepipeds was achieved through hydrothermal treatments of aqueous TiCl3 solutions in the presence of NaCl.

Growth of layered basic zinc acetate in methanolic solutions and its pyrolytic transformation into porous zinc oxide films.

Layered basic zinc acetate (LBZA), Zn(5)(OH)(8)(CH(3)COO)(2).2H(2)O, was deposited on glass substrates by a chemical bath deposition (CBD) method using methanolic solutions of zinc acetate dihydrate. The substrates were put into bottles filled with the solutions and sealed up and were kept at 60 degrees C in a drying oven.