Interfacial molecular regulation of TiO for enhanced and stable cocatalyst-free photocatalytic hydrogen production.

On the basis of the inherent property limitations of commercial P25-TiO, many surface interface modification methods have attracted substantial attention for further improving the photocatalytic properties. However, current strategies for designing and modifying efficient photocatalysts (which exhibit complicated manufacturing processes and harsh conditions) are not efficient for production that is low cost, is nontoxic, and exhibits good stability; and therefore restrict practical applications. Herein, a facile and reliable method is reported for in situ amine-containing silane coupling agent functionalization of commercial P25-TiO by covalent surface modification for constructing a highly efficient photocatalyst.

Effect of Vanadium Oxide on the Crystallization of CaO-AlO-SiO Glass.

This study investigated the effect of vanadium oxide on the crystallization of CaO-AlO-SiO (CAS) glass. Specifically, this study subjected CAS glass-ceramics (GCs) with precipitated hexagonal platy particles of metastable CaAlSiO (CAS GC-H), a layered crystal, that was prepared using metallic molybdenum (Mo) particles as nucleation agents. When the parent glass of CAS GC-H was crystallized with the addition of vanadium oxide in the 0.

Effect of carbon on the co-presence of metallic tungsten as a nucleation agent and Eu in glass: crystallization of CaO-AlO-SiO glass probed with Eu luminescence.

This study demonstrated simple redox control in glasses by improving the method used to added glass raw materials. Specifically, the effect of carbon on the co-presence of metallic tungsten (W) particles as nucleation agents and Eu ions in CaO-AlO-SiO (CAS) glass was investigated their crystallization to form CAS glass-ceramics (GCs). In this study, the glass specimens were prepared by mixing glass cullet containing metallic W particles and Eu ions, respectively, with a glass batch containing carbon.

Microstructural Control of CaO-AlO-SiO Glass Ceramics by Oxidation and Mixing with Nucleation Agents.

Microstructural control of CaO-AlO-SiO (CAS) glass ceramics (GCs) was achieved by oxidation and mixing with nucleation agents. CAS GCs were precipitated with hexagonal platy particles of metastable CaAlSiO layered crystals (CAS GC-H), which are typically prepared under a reductive atmosphere that forms metallic Mo or W particles as nucleation agents. The average particle size of crystals decreased significantly from 50 to 11 μm when the CAS GC-H containing metallic W particles was prepared under an oxidative atmosphere.

Photoreduction of Copper Ions Using Silica-Surfactant Hybrid and Titanium (IV) Oxide under Sulfuric Acid Conditions.

Photoreduction of Cu ions to Cu metal by titanium(IV) oxide (TiO) was conducted in the presence of a silica-surfactant hybrid under sulfuric acid conditions. After irradiation, a dark-red color, reflections due to Cu metal in the X-ray diffraction pattern, and peaks due to Cu 2 and 2 in the X-ray photoelectron spectrum indicated the precipitation of Cu metal in the product. In addition, an increase in the Brunauer-Emmett-Teller specific surface area from 36 and 45 m/g for the silica-surfactant and TiO, respectively, to 591 m/g for the product, and a decrease in the intensity of the C-H stretching band in the Fourier-transform infra-red spectra implied the removal of surfactant during the reaction.

Assessment of the Crystallization Process of CaO-AlO-SiO Glass Probed with Tb Luminescence.

The ratio of the intensity of Tb fluorescence at 543 nm because of an electric dipole transition (D-F) relative to that at 437 nm due to a magnetic dipole transition (D-F) was determined to be proportional to the amount of metastable CaAlSiO crystals precipitated in CaO-AlO-SiO glass. The present results indicate that Tb luminescence can be used as a probe to evaluate the crystallization of glass.

Effect of kaolinite edge surfaces on formation of Tb-doped phosphor by solid-state reaction.

This study assessed the effect of kaolinite edge surfaces on solid-state reactions. Specifically, Tb-doped metastable CaAlSiO showing green phosphorescence was prepared a solid-state reaction between expanded kaolinite, a methoxy-modified kaolinite, having Tb ions adsorbed on its edge surfaces and CaCO. This material cannot be obtained by the conventional grinding of kaolinite, CaCO and TbO, indicating that the use of kaolinite edge surfaces is advantageous as a means of achieving certain solid-state reactions.

Enhanced Hydrogen Production at Optimum pH for the Recovery Cycle of β-FeOOH.

In the photo-Fenton reaction, highly reactive oxygen species are generated on UV irradiation of β-FeOOH, which contributes significantly to hydrogen production. The production process was performed by adjusting the pH of the solution. The effect of acid concentration on hydrogen production was analyzed in this study, and the difference in the amount of hydrogen gas produced in each sample with different pH values was determined.

Effects of kaolinite layer expansion and impurities on the solid-state reaction of kaolinite.

Expanded kaolinite without impurities was found to serve as a suitable raw material for the rapid formation of metastable CaAlSiO with the suppression of byproduct formation. This was accomplished based on the solid-state reaction of the kaolinite with calcium carbonate promoted by mechanical grinding.

Expansion of orderly stacked metakaolinite layers and order destruction using a kaolinite-tetraphenylphosphonium chloride intercalation compound.

The expansion of metakaolinite layers with stacking order and the order destruction were examined by the heat treatment of a kaolinite-tetraphenylphosphonium chloride intercalation compound (Kaol-TPhPCl) at 540 °C under a nitrogen atmosphere followed by the manual grinding of the product using a mortar and a pestle. Fourier-transform infrared spectroscopy and solid-state Al nuclear magnetic resonance spectroscopy with magic angle spinning revealed the kaolinite dehydroxylation. Moreover, the absence of kaolinite diffraction lines and the appearance of the 1.

Regioselective Approach to Characterizing Increased Edge Availability in Layered Crystal Materials following Layer Expansion: Reaction of Kaolinite with Octadecyltrimethylammonium Salts.

In this paper, the regioselective reactions of kaolinite and methoxy-modified kaolinite (MeO-Kaol), methanol-expanded kaolinite, with octadecyltrimethylammonium salts are compared. This study mainly concerns the reactions of kaolinite or MeO-Kaol with octadecyltrimethylammonium chloride (C18TAC) in methanol and the subsequent exhaustive washing of the resultant products with ethanol. X-ray diffraction patterns of the products reveal no intercalation of C18TAC between pristine kaolinite layers.

Rod-Shaped β-FeOOH Synthesis for Hydrogen Production under Light Irradiation.

Renewable energy is spotlighted as a resource to replace fossil fuels, and among the resources, active research on hydrogen energy is ongoing. Various methods have been developed to produce hydrogen energy using photoreduction processes. In this study, we synthesized β-phase iron oxyhydroxide (β-FeOOH) using a hydrothermal method with an optimal synthesis time and investigated its photofunctional properties, including hydrogen production.

Complete decomposition of sulfamethoxazole during an advanced oxidation process in a simple water treatment system.

A simple water treatment system consisting of a deep UV light (λ = 222 nm) source, a mesoporous TiO/boron-doped diamond (BDD) photocatalyst, and a BDD electrode was prepared and used to decompose sulfamethoxazole (SMX) in an advanced oxidation process. The mesoporous TiO/BDD photocatalyst used with the electrochemical treatment promoted SMX decomposition, but the mesoporous TiO/BDD photocatalyst alone had a similar ability to decompose SMX as photolysis. Fragments produced through photocatalytic treatment were decomposed during the electrochemical treatment and fragments produced during the electrochemical treatment were decomposed during the photocatalytic treatment, so performing the electrochemical and photocatalytic treatments together effectively decomposed SMX and decrease the total organic carbon concentration to a trace.

Synthesis of a mesoporous titania thin film with a pseudo-single-crystal framework by liquid-phase epitaxial growth, and enhancement of photocatalytic activity.

A mesoporous titania thin film with a pseudo-single-crystal framework was synthesized on a lanthanum aluminate single-crystal substrate by a surfactant-assisted sol-gel method and liquid-phase epitaxial growth. The crystal lattices were well aligned within the titania framework. The highly energetic {001} facet was exposed on the top surface, which significantly enhanced the photocatalytic activity.

One-Pot Synthesis of Anatase, Rutile-Decorated Hydrogen Titanate Nanorods by Yttrium Doping for Solar H Production.

We have prepared yttrium (Y)-doped hydrogen titanate nanorods (HTN) by a microwave-assisted hydrothermal method. Y-doped HTN showed much improved photocatalytic activities for both H evolution and dye decomposition. H production from a methanol-water solution under UV-visible light for 7 h was enhanced by a factor of 5.

Fabrication of a Silica-Silica Nanoparticle Monolayer Array Nanocomposite Film on an Anodic Aluminum Oxide Substrate and Its Optical and Tribological Properties.

The fabrication and properties of silica nanoparticle monolayer arrays (SNMAs) immobilized on silica films on nanoporous anodic aluminum oxide (AAO) substrates by polymerization of silicic acid and a two-step spin-coating technique are reported. Reflection spectra of the obtained silica-SNMA nanocomposite films on AAO substrates were almost the same as those of the original AAO substrate. The coefficient of friction at an applied load of 0.

Synergetic effect in water treatment with mesoporous TiO/BDD hybrid electrode.

Boron-doped diamond (BDD) electrodes have a wide potential window and can produce ozone by water electrolysis at high voltage. Though ozone has strong oxidative power (standard oxidation potential: 2.07 V NHE), it cannot decompose certain types of recalcitrant organic matter completely.

Hydrogen Production System by Light-Induced α-FeOOH Coupled with Photoreduction.

Solar-driven catalysts on semiconductors to produce hydrogen are considered as a means to solve environmental issues. In this study, H production coupling with oxygen consumption by noble metal-free α-FeOOH was demonstrated even though the conduction band edge was lower than the reduction potential of H to H . For activation of α-FeOOH, an electron donor, Hg-Xe irradiation, and low pH (ca.

Denaturation of Lysozyme with Visible-light-responsive Photocatalysts of Ground Rhodium-doped and Ground Rhodium-antimony-co-doped Strontium Titanate.

Protein denaturants play an important role in medical and biological research, and development of new denaturants is widely explored to study aging and various diseases. In this research, we treated lysozyme, a model protein, with photocatalysts of ground Rh-doped SrTiO (g-STO:Rh) and ground Rh-Sb-co-doped SrTiO (g-STO:Rh/Sb) under visible light irradiation to explore the potential of those photocatalysts as denaturants. SDS-PAGE showed that photocatalysis with g-STO:Rh induced the fragmentation of lysozyme into unidentifiable decomposition products.

Synthesis of Mesoporous TiO₂/Boron-Doped Diamond Photocatalyst and Its Photocatalytic Activity under Deep UV Light (λ = 222 nm) Irradiation.

There is a need for highly efficient photocatalysts, particularly for water purification. In this study, we fabricated a mesoporous TiO₂ thin film on a boron-doped diamond (BDD) layer by a surfactant-assisted sol-gel method, in which self-assembled amphiphilic surfactant micelles were used as an organic template. Scanning electron microscopy revealed uniform mesopores, approximately 20 nm in diameter, that were hexagonally packed in the TiO₂ thin film.

Multifunctionality in coating films including Nb-doped TiO and Cs WO: near infrared shielding and photocatalytic properties.

Various types of coating films were obtained from hydrothermally synthesized Nb-doped TiO (NTO) and Cs WO (CWO) nanoparticles. The coating films possessed multifunctionality including near infrared (NIR) absorption and photocatalysis abilities. The NTO and CWO nanoparticles were synthesized by a unique solvothermal reaction in which water induced by an esterification reaction between alcohol and carboxylic acid can act as a hydrolyzing agent for metal precursors.

Solution Plasma Process-Derived Defect-Induced Heterophase Anatase/Brookite TiO Nanocrystals for Enhanced Gaseous Photocatalytic Performance.

We report a simple room-temperature synthesis route for increasing the reactivity of a TiO photocatalyst using a solution plasma process (SPP). Hydrogen radicals generated from the SPP chamber interact with the TiO photocatalyst feedstock, transforming its crystalline phase and introducing oxygen vacancy defects. In this work, we examined a pure anatase TiO as a model feedstock because of its photocatalytic attributes and well-characterized properties.

Selective Inactivation of Bacteriophage in the Presence of Bacteria by Use of Ground Rh-Doped SrTiO Photocatalyst and Visible Light.

Bacteriophage (denoted as phage) infection in the bacterial fermentation industry is a major problem, leading to the loss of fermented products such as alcohol and lactic acid. Currently, the prevention of phage infection is limited to biological approaches, which are difficult to apply in an industrial setting. Herein, we report an alternative chemical approach using ground Rh-doped SrTiO (denoted as g-STO:Rh) as a visible-light-driven photocatalyst.