Photodegradation of Rhodamine B in Water Assisted by Titania Nanorod Thin Films Subjected to Various Thermal Treatments

Well-crystallized titania nanorod thin films with high specific surface areas were synthesized through in situ oxidation of metallic titanium substrates with hydrogen peroxide solutions at a low temperature of 80 °C. The effects of thermal treatments on the ability of the thin films to assist photodegradation of rhodamine B in water were studied in detail. It is found that, due to a unique nanofeature, the titania nanorod film retained its small grain size and high specific surface area during the subsequent thermal treatment for up to 450 °C, which further improved the crystallinity of titania. In addition, upon heating to 450 °C, the nanorods still possessed a high surface fractal dimension, which is an indication of high surface roughness and surface area. As a result, the photocatalytic activity of the titania nanorod film is found to increase with an increasing heating temperature for up to 450 °C. The subsequent thermal treatment at temperatures beyond 450 °C decreased the photocatalytic activity, because of the significantly reduced specific surface area. The current investigation provided a simple and easily scaled-up approach to produce photocatalysts for efficient removal of dye effluents in wastewater

Catalyzed Degradation of Azo Dyes under Ambient Conditions

Phase-pure layered perovskite La4Ni3O10 powders were synthesized by a solution combustion approach. It is found that, in the presence of the La4Ni3O10 powders, aqueous azo dyes can be degraded catalytically and efficiently under ambient conditions. Neither light nor additional reagents are needed in the catalytic reaction. The dye degradation procedure can be accelerated markedly by magnetic stirring. A systemic series of chemical and electrochemical experiments suggested that the dye degradation proceeds through electron transfers from the dye molecules to the catalyst and then to electron acceptors such as dissolved oxygen. The present catalytic degradation requires no additional reagents or external energy input, which hence provides a potentially low-cost alternative for the remediation of azo-dye effluents

Eruption Combustion Synthesis of NiO/Ni Nanocomposites with Enhanced Properties for Dye-Absorption and Lithium Storage

Large-scale energy-efficient productions of oxide nanoparticles are of great importance in energy and environmental applications. In nature, volcano eruptions create large amounts of volcano ashes within a short duration. Inspired by such phenomena, we report herein our first attempt to achieve an artificial volcano for mass productions of various oxide nanoparticles with enhanced properties for energy and environmental applications. The introduction of NaF into the solution combustion synthesis (SCS), which is a generally adopted synthetic route for mass productions of various oxide nanoparticles, results in better particle dispersity and a drastic increase in specific surface area compared to the conventional SCS. In a fixed dosage of NaF, a new eruption combustion pattern emerges, which may be contributed to the more gas evolution, lower apparent density, and weaker interparticle force. The novel eruption combustion pattern observed in SCS provides a versatile alternative for SCS to control combustion behavior, microstructure, and property of the products. NiO/Ni nanocomposite yielded by the new approach shows an ideal dye-absorption ability as well as lithium storage capacity. The new SCS pattern reported in this paper is versatile, emerging in various systems of Ni–Co–O, Co–O, La–O, Ni–Co–O, Zn–Co–O, and La–Ni–O

Eruption Combustion Synthesis of NiO/Ni Nanocomposites with Enhanced Properties for Dye-Absorption and Lithium Storage

Large-scale energy-efficient productions of oxide nanoparticles are of great importance in energy and environmental applications. In nature, volcano eruptions create large amounts of volcano ashes within a short duration. Inspired by such phenomena, we report herein our first attempt to achieve an artificial volcano for mass productions of various oxide nanoparticles with enhanced properties for energy and environmental applications. The introduction of NaF into the solution combustion synthesis (SCS), which is a generally adopted synthetic route for mass productions of various oxide nanoparticles, results in better particle dispersity and a drastic increase in specific surface area compared to the conventional SCS. In a fixed dosage of NaF, a new eruption combustion pattern emerges, which may be contributed to the more gas evolution, lower apparent density, and weaker interparticle force. The novel eruption combustion pattern observed in SCS provides a versatile alternative for SCS to control combustion behavior, microstructure, and property of the products. NiO/Ni nanocomposite yielded by the new approach shows an ideal dye-absorption ability as well as lithium storage capacity. The new SCS pattern reported in this paper is versatile, emerging in various systems of Ni–Co–O, Co–O, La–O, Ni–Co–O, Zn–Co–O, and La–Ni–O

Eruption Combustion Synthesis of NiO/Ni Nanocomposites with Enhanced Properties for Dye-Absorption and Lithium Storage

Large-scale energy-efficient productions of oxide nanoparticles are of great importance in energy and environmental applications. In nature, volcano eruptions create large amounts of volcano ashes within a short duration. Inspired by such phenomena, we report herein our first attempt to achieve an artificial volcano for mass productions of various oxide nanoparticles with enhanced properties for energy and environmental applications. The introduction of NaF into the solution combustion synthesis (SCS), which is a generally adopted synthetic route for mass productions of various oxide nanoparticles, results in better particle dispersity and a drastic increase in specific surface area compared to the conventional SCS. In a fixed dosage of NaF, a new eruption combustion pattern emerges, which may be contributed to the more gas evolution, lower apparent density, and weaker interparticle force. The novel eruption combustion pattern observed in SCS provides a versatile alternative for SCS to control combustion behavior, microstructure, and property of the products. NiO/Ni nanocomposite yielded by the new approach shows an ideal dye-absorption ability as well as lithium storage capacity. The new SCS pattern reported in this paper is versatile, emerging in various systems of Ni–Co–O, Co–O, La–O, Ni–Co–O, Zn–Co–O, and La–Ni–O

Colonoscopic findings reveal two fistulae () at the distal transverse colon

<p><b>Copyright information:</b></p><p>Taken from "Gastrojejunocolic fistula after gastrojejunostomy: a case series"</p><p>http://www.jmedicalcasereports.com/content/2/1/193</p><p>Journal of Medical Case Reports 2008;2():193-193.</p><p>Published online 4 Jun 2008</p><p>PMCID:PMC2424061.</p><p></p

Left: The Urograffin enema demonstrating early contrast filling of the stomach and jejunum

, stomach; , jejunum; , transverse colon. Right: The barium meal shows the jejunum and colon simultaneously.<p><b>Copyright information:</b></p><p>Taken from "Gastrojejunocolic fistula after gastrojejunostomy: a case series"</p><p>http://www.jmedicalcasereports.com/content/2/1/193</p><p>Journal of Medical Case Reports 2008;2():193-193.</p><p>Published online 4 Jun 2008</p><p>PMCID:PMC2424061.</p><p></p

A Dual-Layer Titania Film with Enhanced Photocatalytic Activity

A dual-layer titania film consisting of a sol−gel anatase layer over an interconnected porous anatase one was fabricated and its photoelectrochemical behavior as well as photocatalytic ability were studied in detail. The porous layer was fabricated through direct oxidation of a metallic Ti substrate with an aqueous hydrogen peroxide at 80 °C for 1 h. The Ti substrate with the porous titania layer was then subjected to a sol−gel spin-coating to deposit the upper titania layer. The dual-layer titania film as a whole was phase pure anatase after a subsequent thermal treatment at 450 °C. The UV−vis diffuse reflectance spectra and ambient photoluminescence spectra indicated that the porous anatase possessed a band gap width narrower than that of the sol−gel derived anatase, which was attributed to the relatively larger amounts of surface oxygen deficiency. Under UV illumination, both the saturated photocurrent and the activity to assist photodegradation of rhodamine B in water were nearly double that of the simply summation of those exhibited by the two component layers alone for the dual-layer film. The photocatalytic activity of the dual-layer film was even 3.5 times that of the sol−gel derived anatase film with identical film weight. This work demonstrates that an appropriate configuration of two titania layers derived by distinct routes, even if the titania is of the same crystal structure such as anatase, is possible to improve significantly the photoelectrochemical response as well as the photocatalytic activity, providing that the band gap of each titania is aligned properly so that the charge separation efficiency can be enhanced significantly

A H₂O₂ Oxidation Approach to Ti₃C₂/TiO₂ for Efficient Photocatalytic Removal of Distinct Organic Pollutants in Water

To develop versatile photocatalysts for efficient degradation of distinct organic pollutants in water is a continuous pursuit in environment remediation. Herein, we directly oxidize Ti3C2 MXene with hydrogen peroxide to produce C-doped anatase TiO2 nanowires with aggregates maintaining a layered architecture of the MXene. The Ti3C2 MXene provides a titanium source for TiO2, a carbon source for in situ C-doping, and templates for nanowire aggregates. Under UV light illumination, the optimized Ti3C2/TiO2 exhibits a reaction rate constant 1.5 times that of the benchmark P25 TiO2 nanoparticles, toward photocatalytic degradations of trace phenol in water. The mechanism study suggests that photogenerated holes play key roles on the phenol degradation, either directly oxidizing phenol molecules or in an indirect way through oxidizing first the surface hydroxyl groups. The unreacted Ti3C2 MXene, although with trace amounts, is supposed to facilitate electron transfer, which inhibits charge recombination. The unique nanostructure of layered aggregates of nanowires, abundant surface oxygen vacancies arising from the carbon doping, and probably the Ti3C2/TiO2 heterojunction guarantee the high photocatalytic efficiency toward removals of organic pollutants in water. The photocatalyst also exhibits an activity superior to, or at least comparable to, the benchmark P25 TiO2 toward photodegradations for typical persistent organic pollutants of phenol, dye molecule of rhodamine B, antibiotic of tetracycline, pharmaceutical wastewater of ofloxacin, and pesticide of N,N-dimethylformamide, when evaluated in total organic carbon removal

Surface-Induced Desolvation of Hydronium Ion Enables Anatase TiO₂ as an Efficient Anode for Proton Batteries

Hydrogen ion is an attractive charge carrier for energy storage due to its smallest radius. However, hydrogen ions usually exist in the form of hydronium ion (H3O+) because of its high dehydration energy; the choice of electrode materials is thus greatly limited to open frameworks and layered structures with large ionic channels. Here, the desolvation of H3O+ is achieved by using anatase TiO2 as anodes, enabling the H+ intercalation with a strain-free characteristic. Density functional theory calculations show that the desolvation effects are dependent on the facets of anatase TiO2. Anatase TiO2 (001) surface, a highly reactive surface, impels the desolvation of H3O+ into H+. When coupled with a MnO2 cathode, the proton battery delivers a high specific energy of 143.2 Wh/kg at an ultrahigh specific power of 47.9 kW/kg. The modulation of the interactions between ions and electrodes opens new perspectives for battery optimizations