Enhanced Photocatalytic Degradation of Indoor Low Concentration Gaseous Formaldehyde by Asymmetric Silveriodate Composited with 2D or 3D Bismuth Oxybromide.

Formaldehyde is one of the most hazardous and typical indoor VOCs air pollutants. Asymmetric AgIO3 was respectively composited with 3D hierarchically structured BiOBr and 2D BiOBr nanosheets to photodegrade gas-phase formaldehyde. Ag/AgIO3 /BiOBr(CMC) demonstrated better photocatalytic performance than Ag/AgIO3 /BiOBr owning to the role of biomass solvent sodium carboxymethyl cellulose in increasing the specific surface area, reducing the band gap and changing the dominant facets. Moreover, Ag nanoparticles coming from the reduction in AgIO3 were confirmed by XRD, SEM and XPS. The surface plasma resonance effect of Ag NPs improved the efficiency of the light quantum. Besides, different exposed facets of {010} in BiOBr(CMC) and {001} in BiOBr resulted in distinct oxygen vacancy structures. O 2 2 - could be generated via a two-electron transfer pathway on the {010} dominant facets surface in AABR-CMC, leading to the change in photolysis pathway and facilitating more · OH produced by AABR-CMC. Compared with pure AgIO3 and BiOBr or BiOBr(CMC), the photocatalytic efficiency of the composites was improved significantly. Optimal photodegradation efficiency for HCHO was achieved for AABR-75 and AABR-CMC50.

One-step emulsification for controllable preparation of ethyl cellulose microcapsules and their sustained release performance.

A simple and versatile strategy for controlled production of monodisperse ethyl cellulose (EC) microcapsules by a single-stage emulsification method has been developed. Monodisperse oil-in-water emulsions, obtained by a microfluidic device, are used as templates for preparing EC microcapsules. Oil-soluble ethyl acetate (EA) is miscible with water, so the interfacial mass transfer between EA and water occurs sufficiently, which leads to water molecules pass through the phase interface and diffuse into emulsion interior. Water molecules aggregate at the interface, and some merge into a large water drop in the central position of the emulsion. After evaporation of EA solvent, monodisperse EC microcapsules create large numbers of pits on the surface with a hollow structure. Curcumin is used as a model drug and embedded in the hollow structure. EC microcapsules have good, sustained drug release efficacy in a simulated intestinal environment, and the release process of EC microcapsules containing 6.14% drug-loaded capacity is fully consistent with the vitro drug release model. Such simple techniques for making EC microcapsules may open a window to the controlled preparation of other multifunctional microcapsules. Besides, it offers theoretical guidance for the study of EC microcapsules as drug carriers and expanding clinical application of curcumin.

Construction of g-C3N4-BiOBrxI1-x Nanocomposites with Tunable Energy Band Structure for Enhanced Visible Light Photocatalytic CO2 Reduction.

The g-C3N4-BiOBrxI1-x nanocomposites were successfully prepared using solvothermal methods. The obtained g-C3N4-BiOBrxI1-x composites had tunable band structures and displayed preferable photocatalytic performance for CO2 reduction irradiated by visible light. Moreover, comparing to pure g-C3N4 and corresponding BiOBrxI1-x, all the obtained g-C3N4-BiOBrxI1-x nanocomposites exhibited distinctly higher activity for CO2 reduction, with 5% g-C3N4-BiOBr0.25I0.75 nanocomposites displaying the best photocatalytic performance. Enhanced photocatalytic performance of g-C3N4-BiOBrxI1-x nanocomposites may arrive from their advantages of high efficiency of electron-hole separation, tunable band structures, and rapid charge transfer. Moreover, a possible visible light induced photocatalytic mechanism on g-C3N4-BiOBrxI1-x nanocomposites was further proposed.

One-Pot Facile Synthesis of AgIO3/Ag2O/Ag Nanocomposites with Enhanced Photocatalytic Activity.

AgIO3/Ag2O/Ag nanocomposites with enhanced photocatalytic activities were synthesized by a onestep coprecipitation method at room temperature. The optimum hybrid of AgIO3/Ag2O = 1.25:1 with Ag nanoparticles (Ag NPs) loading (denoted as AA125) exhibited superior photocatalytic activity, demonstrating 97.19% tetracycline (TC) degradation within 60 min under simulated solar irradiation. This was approximately 10.44 and 2.63 times higher than that of pure Ag2O and AgIO3, respectively. The advanced photocatalytic activity can be ascribed to the synergetic effects of the heterostructured AgIO3/Ag2O/Ag and the strong surface plasmon resonance (SPR) effect of Ag NPs generated on the surface, which improved the separation and transfer efficiency of photoinduced electron-hole pairs. The results from radical scavenger experiments indicated that the degradation of TC was driven mainly by the participation of superoxide radical (·O-2).

A Novel CdWO4/BiOCl p-n Heterojunction Nanocomposites with Excellent Photocatalytic Activity Under Simulated Solar Light.

Constructing heterojunction is an effective way to enhance the catalytic activities of semiconductor photocatalyst owing to its special synergistic effect. In this study, a novel p-n heterostructured CdWO4/BiOCl nanocomposites were synthesized by a facile hydrothermal and subsequently chemistry bath method. The photocatalytic performance of CdWO4/BiOCl heterojunctions was investigated by degrading phenol and RhB under simulated solar light irradiation. Highly improved photocatalytic activities were achieved on all CdWO4/BiOCl heterojunctions compared with both pure CdWO4 and BiOCl. The CdWO4/BiOCl heterojunction with optimal mole ratio of 25% CdWO4 displayed the highest photoactivity with RhB and phenol being completely degraded in 15 min and 6 h, respectively. Mechanism analysis revealed that the interface of p-n heterojunction of CdWO4/BiOCl composites can produce spontaneously electric field which can effectively separate photogenerated electrons and holes. Moreover, the active species research demonstrated that holes and superoxide radicals proved to be the principal active species during the photocatalytic process. This work demonstrated that the CdWO4/BiOCl photocatalyst may be a promising material for purifying the organic contaminant in practical application.

Biomass Assisted Synthesis of 3D Hierarchical Structure BiOX(X Cl, Br)-(CMC) with Enhanced Photocatalytic Activity.

3D hierarchical structure BiOX(X ═ Cl, Br)-(CMC) assembled from 2D nanosheets with {010} facets exposed have been successfully synthesized by the assistance of biomass solvent CMC-Na. All the nitrogen adsorption isotherms and photoelectrochemical results reflected that BiOX(X Cl, Br)-(CMC) exhibit higher specific surface area, superior optical absorption efficiency and separation efficiency of photoinduced electron-hole than BiOX(X═Cl, Br) 2D nanosheets exposed with {001} facets. Besides, 96.5% and 60.3% of tetracycline hydrochloride (TC) were photodegradated in 60 minutes under the visible light irradiation catalyzed by BiOBr-(CMC) and BiOCl-(CMC), which is much better than BiOBr and BiOCl. The formation and enhanced photocatalytic activity of 3D hierarchical structure BiOX-(CMC) may be ascribe to the bi-functional groups of CMC, which can affect the crystallization process and morphology of BiOX. According to the merit of environmental friendly and improved photocatalytic activity of the 3D hierarchitecture, we believe that this work broadens the possibility of designing efficient BiOX photocatalyst with {010} facets exposed.

Electrochemical Sensor Based on Platinum Nanoparticles Modified Graphite-Like Carbon Nitride for Detection of Phenol.

In this work, platinum nanoparticles were modified on graphite-like carbon nitride (g-C3N4) surface via a simple one-pot deposition reduction method, and the prepared Pt/g-C3N4 was used as electrode materials for phenol sensing. The morphology and crystallographic structure of Pt/g-C3N4 were characterized by Scanning transmission electron microscope (STEM) and X-ray diffraction (XRD). The electrochemical performance of Pt/g-C3N4 toward phenol was investigated in details and the results showed that the Pt/g-C3N4 sensor had favorable sensing ability for phenol detection. Under the optimum parameters, the electrochemical sensor had a wide range of 2 to 20 µM, lower detection limits of 0.667 µM (S/N═3), and higher sensitivity of 1.21084 mA µM-1 in phenol detection, indicating the excellent capability of the newly developed sensor to determine phenol. Moreover, the design of the Pt/g-C3N4 sensor may provide a potential material for actual application in phenol detection due to its merits of simplicity, reliability, sensitivity and low-cost.

Synthesis and enhanced visible light photocatalytic CO2 reduction of BiPO4-BiOBr x I1-x p-n heterojunctions with adjustable energy band.

A series of novel BiPO4-BiOBr x I1-x p-n heterojunctions were successfully prepared by a facile solvothermal method. The morphology, structure and optical properties of photocatalysts were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD) and ultraviolet visible diffuse reflectance spectroscopy. The visible light photocatalytic activities of BiPO4-BiOBr x I1-x heterojunctions were investigated by photocatalytically reducing CO2. After 4 hours of irradiation, the 5% BiPO4-BiOBr0.75I0.25 heterojunction showed the highest photocatalytic activity with the yields of CO and CH4 up to 24.9 and 9.4 µmol gcat -1 respectively. The improved photocatalytic activity may be due to the formation of BiPO4-BiOBr x I1-x p-n heterojunctions which can effectively restrict the recombination rate of the photoexcited charge carriers. Moreover, the energy band structure of BiPO4-BiOBr x I1-x heterojunctions could be easily adjusted by changing the mole ratio of I and Br. The possible mechanism of the enhancement of the photocatalytic performance was also proposed based on experimental and theoretical analysis. The present study may provide a rational strategy to design highly efficient heterojunctions with an adjustable energy band for environmental treatment and energy conversion.

A Novel Heterojunction AgI/WO3 Nanocomposite with the Highly Enhanced Photocatalytic Activity.

Herein, a novel visible-light-driven heterojunction AgI/WO3 nanocomposite was successfully prepared using a facile two-step hydrothermal-precipitation process and applied for photodegradation of organic pollutants. The information of phase structures, morphology, optical properties of the asprepared samples was analysed in detail by XRD, TEM, EDS, STEM, DRS measurement and so on. Formation of the heterostructure and intimate interactions between AgI and WO3 can promote highly effective photogenerated electron-hole pairs separation, which enable the heterojuctions to perform excellent photocatalytic activity as greatly enhanced photocatalysts compared to that of pristine AgI and WO3 for decomposing Rhodamine B (RhB) dye under visible light irradiation. In addition, the AgI/WO3 (1:1) nanocomposites exhibit optimal photocatalytic activity. Moreover, the as-prepared samples exhibit good stability, which is favorable for its potential application. Additionally, we have an analysis on a possible photocatalytic mechanism based on trapping experiments together with other experimental results.

An Innovative Electrochemical Sensor Ground on NiO Nanoparticles and Multi-Walled Carbon Nanotubes for Quantitative Determination of Nitrite.

An electrochemical sensor ground on nickel oxide (NiO) nanoparticles and multi-walled carbon nanotubes (MWCNTs) was exploited for the detection of nitrite. Scanning electron microscopy (SEM) ensure the morphology of the nanocomposite consisted of NiO nanoparticle and MWCNTs. High Resolution Transmission electron microscopy (HR-TEM) reveals that the structure of NiO nanoparticles and MWCNTs. Scanning transmission electron microscopy (STEM) persuasively verified presence of the C, Ni and O element. The electrochemical character of the nanocomposite were researched by cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS), and the behavior of electrochemical oxidation to nitrite on NiO/MWCNTs/CP was explored by chronoamperometry. In tests, the NiO/MWCNTs/CP shown a sensitive current response toward nitrite, the oxidation peak current are linearly related to nitrite concentration in the range from 10-6 M to 10-4 M (R = 0.997) with a sensitivity of 3.53 µA µM-1 and a detection limit of 0.25 µM (S/N = 3). The validity of utilizing the proposed electrode to determine nitrite in tap water was also demonstrated.

Enhanced Visible-Light-Responsive Photocatalytic Properties of Bi2MoO6-BiOCl Nanoplate Composites.

Bi2MoO6-BiOCl nanoplate composites were successfully synthesized by a simple solvothermal process. The morphology, microstructure and optical properties of the as-prepared Bi2MoO6-BiOCl nanocomposites were characterized using transmission electron microscopy (TEM), X-ray diffraction (XRD) and UV-Vis diffuse reflection spectroscopy (DRS). A noteworthy enhancement in the visible-light-responsive photocatalytic degradation of RhB was observed over the Bi2MoO6-BiOCl nanocomposites compared to its individual components. The enhanced photocatalytic performance of Bi2MoO6-BiOCl nanocomposites could be attributed to the heterojunction interface in the composite, which can both efficiently separate photogenerated electron-hole pairs and also restrain the recombination of photoinduced charges.

Electrocatalysis and Detection of Nitrite on a Pd/Fe2O3 Nanocomposite Modified Glassy Carbon Electrode.

An electrochemical palladium/ferric oxide (Pd/Fe2O3) nanocomposite modified glassy carbon electrode (GCE) was fabricated by hydrothermal method of Fe2O3 and electrochemical deposition of palladium nanoparticles, respectively. As-prepared Pd/Fe2O3 composite modified electrode exhibits enhanced electrocatalytic activity towards the catalytic oxidation of nitrite compared to Fe2O3, PdNPs modified electrodes and bare electrode. The parameters such as the influence of amount of Pd nanoparticles deposition onto the Pd/Fe2O3 modified electrode (ME) and effect of solution pH were investigated and discussed in detail. Under the optimal conditions, the Pd/Fe2O3 modified GCE can be used to detect nitrite concentration in a wide linear range of 10 and 1000 µM with the detection limit of 0.1 µM. The presence of Cu2+, Na+, Cl-, PO3-4 SO2-4, Mg2+ K+, NO-3, and NH+4 showed a trivial effect on the response of nitrite determination, revealing that developed modified electrode has an excellent anti-interference ability to common ions. It also shows good stability and reproducibility.

Novel C3N4/Zn(1-x)Cd(x)S heterostructures with adjustment of the band gap and their visible light photocatalytic properties.

In this study, C3N4/Zn(1-x)Cd(x)S (0 ≤ x ≤ 1) heterostructures with adjustment of the band gap were successfully prepared by calcination and a hydrothermal synthesis method. The photocatalytic properties of C3N4/Zn(1-x)Cd(x)S composite photocatalysts were evaluated by the photocatalytic degradation of RhB under visible light irradiation. The results showed that the combination of the two semiconductor photocatalysts (C3N4 and Zn(1-x)Cd(x)S) greatly enhanced the photocatalytic degradation efficiency of RhB compared to the pure C3N4 and Zn(1-x)Cd(x)S under visible light irradiation. Among them, the 0.1C3N4/Zn0.8Cd0.2S composite photocatalyst exhibited the highest photocatalytic activities with the degradation efficiency of RhB arriving to 97.9% within 90 min. The remarkable photocatalytic activity of the 0.1C3N4/Zn0.8Cd0.2S composite photocatalyst was mainly attributed to the appropriate band structure and the effective separation of photogenerated electron-hole pairs. Additionally, a possible basic mechanism of the composite semiconductor photocatalytic process was also discussed. Moreover, it was also investigated that O2(˙⁻) and h(+) were the main reactive oxidative species in this photocatalytic process of the degradation of RhB on the 0.1C3N4/Zn0.8Cd0.2S heterostructure photocatalyst.

Photocatalytic activities of Mo-doped Bi2WO6 three-dimensional hierarchical microspheres.

The Mo-doped Bi(2)WO(6) three-dimensional (3D) hierarchical microspheres from nanoplates have been synthesized by a hydrothermal route. The products were characterized in detail by multiform techniques: X-ray diffraction (XRD), energy-dispersive X-ray analysis (EDS), scanning electron microscopy (SEM), and UV-vis absorption spectrum. The results of the photocatalytic degradation of Rhodamine-B (RhB) in aqueous solution showed that molybdenum ions doping greatly improved the photocatalytic efficiency of Bi(2)WO(6) 3D hierarchical microspheres. The Mo-doped Bi(2)WO(6) microspheres with atomic ratio of Mo-W of 0.05 had the best activity in photodegradation of RhB in aqueous solution under 500 W Xe lamp light irradiation.

Green synthesis and catalytic function of tungsten oxide nanoparticles.

In this paper, a green chemical synthetic route was developed to synthesize WO3 nanoparticles with an average size of 70 nm. The products were characterized in detail by multiform techniques: X-ray diffraction (XRD), energy-dispersive X-ray analysis (EDS), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). The photoluminescence of the obtained WO3 nanoparticles was also investigated. The effects of the hydrothermal temperature on the crystalline phase and morphology of the products have been studied systematically. The photocatalytic activity of the samples was evaluated by photocatalytic decolorization of methylene blue (MB) aqueous solution. The electrocatalytic activity was characterized using voltammetric techniques. The results showed that the obtained WO3 nanoparticles have an excellent photocatalytic and electrocatalytic performance for the MB.

Fabrication and chemical etching of Ag/C nanocables.

In this paper, Ag/C nanocables were synthesized via a one-step simple hydrothermal route by using glucose as reducing agent and carbon source, AgNO3 as silver source. The products are characterized in detail by multiform techniques: X-ray diffraction, energy-dispersive X-ray analysis, scanning electron microscopy, transmission electron microscopy. The results show that the obtained products are coaxial nanocables with lengths of several micrometers, about 200-500 nm in diameter, and a surrounding sheath about 80-100 nm in thickness. Different products including carbonaceous nanotubes and nanocables with fragmentary Ag core were obtained by adjusting time of chemical etching.

Photocatalytic activities of Cd-doped ZnWO4 nanorods prepared by a hydrothermal process.

The ZnWO(4) nanorods doped with cadmium ions have been successfully synthesized by a hydrothermal crystallization process. The products were characterized in detail by multiform techniques: X-ray diffraction (XRD), energy dispersive X-ray analysis (EDS), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). The results of the photocatalytic degradation of rhodamine B (RhB) in aqueous solution showed that cadmium ions doping greatly improved the photocatalytic efficiency of ZnWO(4) nanorods. The Cd-doped ZnWO(4) nanorods with atomic ratio of Cd to Zn being 0.06 had the best activity in photo-degradation of RhB in aqueous solution under UV light irradiation, when the nanorods have prepared at pH 8.

Self-assembly of alpha-MnO2 nanorods into spheres: synthesis and electrochemical properties.

The alpha-MnO2 spherical assemblies were prepared via a facile hydrothermal approach in the presence of sodium dodecyl sulfate (SDS). The assembled nanostructures were composed of the MnO2 nanorods with 150-200 nm in width and several micrometers in length. The products were characterized by SEM, TEM and XRD. The electrochemical characterization was carried out by cyclic voltammetry, which indicated that the alpha-MnO2 spherical assemblies were of an excellent electrode material for supercapacitor.

4,4'-(Propane-1,3-di-yl)dipiperidinium sulfate monohydrate.

In the title compound, C(13)H(28)N(2) (2+)·SO(4) (2-)·H(2)O, extensive hydrogen-bonding inter-actions between the protonated 4,4'-(propane-1,3-di-yl)dipiperidinium ions, the sulfate anions and the water mol-ecules lead to a three-dimensional pillared and layered structure with the 4,4'-(propane-1,3-di-yl)-dipiperidinium ions acting as the pillars.

1,4-Diazo-niabicyclo-[2.2.2]octane terephthalate.

In the title compound, C(6)H(14)N(2+)·C(8)H(4)O(4) (2-), the protonated 1,4-diazo-niabicyclo-[2.2.2]octane cations and the deprotonated terephthalate anions are alternately linked by N-H⋯O hydrogen bonds into chains.