Stereoselective Vinylogous Aza-Pummerer Reaction of β,β-Disubstituted Enesulfinamides.

Treatment of multisubstituted NH-enesulfinamides with tosyl isocyanate (TsNCO) at room temperature results in the formation of α-tosylcarbamoyloxy -sulfenyl ketimines with high enantioselectivity. This process is believed to proceed via a vinylogous aza-Pummerer-type reaction pathway in which the sulfinyl oxygen atom in the enesulfinamides undergoes nucleophilic attack on tosyl isocyanate, triggering the subsequent transformations that enable the transfer of chirality from sulfur to carbon.

S-Scheme BiOCl/MoSe Heterostructure with Enhanced Photocatalytic Activity for Dyes and Antibiotics Degradation under Sunlight Irradiation.

Semiconductor photocatalysis is considered to be a promising technique to completely eliminate the organic pollutants in wastewater. Recently, S-scheme heterojunction photocatalysts have received much attention due to their high solar efficiency, superior transfer efficiency of charge carriers, and strong redox ability. Herein, we fabricated an S-scheme heterostructure BiOCl/MoSe by loading MoSe nanosheets on the surface of BiOCl microcrystals, using a solvothermal method.

Surface-Enhanced Raman Spectroscopy Assisted by Radical Capturer for Tracking of Plasmon-Driven Redox Reaction.

The deep understanding about the photocatalytic reaction induced by the surface plasmon resonance (SPR) effect is desirable but remains a considerable challenge due to the ultrafast relaxation of hole-electron exciton from SPR process and a lack of an efficient monitoring system. Here, using the p-aminothiophenol (PATP) oxidation SPR-catalyzed by Ag nanoparticle as a model reaction, a radical-capturer-assisted surface-enhanced Raman spectroscopy (SERS) has been used as an in-situ tracking technique to explore the primary active species determining the reaction path. Hole is revealed to be directly responsible for the oxidation of PATP to p, p'-dimercaptoazobenzene (4, 4'-DMAB) and O2 functions as an electron capturer to form isolated hole.

Double-diffusion-based synthesis of BiVO4 mesoporous single crystals with enhanced photocatalytic activity for oxygen evolution.

BiVO4 mesoporous single crystals (MSCs) were successfully prepared, for the first time, by a one-step hydrothermal method using the acidified BiVO4 precursor solution pre-impregnated silica as the template. It was revealed that the BiVO4 MSCs were formed by a double-diffusion mechanism. The O2 evolution rate over BiVO4 MSCs was improved nearly 10 times than that over BiVO4 bulk single crystals.

Rhodol-based far-red fluorescent probe for the detection of cysteine and homocysteine over glutathione.

The simultaneous discrimination of cysteine (Cys), homocysteine (Hcy) and glutathione (GSH) is of great importance due to their roles in biology and close link to many diseases, especially via the development of a far-red fluorescent probe that could be used for rapid, selective, and sensitive detection of all three. Herein, we report the characterization of a far-red fluorescent probe with turn-on fluorescence properties and visible color changes that could be used for the detection of cysteine and homocysteine over glutathione. In this study we found that the sensor could discriminate cysteine and homocysteine over glutathione within 20 min.

Core-Shell Structural CdS@SnO₂ Nanorods with Excellent Visible-Light Photocatalytic Activity for the Selective Oxidation of Benzyl Alcohol to Benzaldehyde.

Core-shell structural CdS@SnO2 nanorods (NRs) were fabricated by synthesizing SnO2 nanoparticles with a solvent-assisted interfacial reaction and further anchoring them on the surface of CdS NRs under ultrasonic stirring. The morphology, composition, and microstructures of the obtained samples were characterized by field-emission scanning electron microscopy, transmission electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy, and nitrogen adsorption-desorption. It was found that SnO2 nanoparticles can be tightly anchored on the surface of CdS NRs, and the thickness of SnO2 shells can be conveniently adjusted by simply changing the addition amount of SnO2 quantum dots.

A Brown Mesoporous TiO2-x /MCF Composite with an Extremely High Quantum Yield of Solar Energy Photocatalysis for H2 Evolution.

A brown mesoporous TiO2-x /MCF composite with a high fluorine dopant concentration (8.01 at%) is synthesized by a vacuum activation method. It exhibits an excellent solar absorption and a record-breaking quantum yield (Φ = 46%) and a high photon-hydrogen energy conversion efficiency (η = 34%,) for solar photocatalytic H2 production, which are all higher than that of the black hydrogen-doped TiO2 (Φ = 35%, η = 24%).

Highly-dispersed boron-doped graphene nanoribbons with enhanced conductibility and photocatalysis.

Highly-dispersed boron-doped graphene nanoribbons (B-GNRs), prepared by a simple vacuum activation method, exhibit p-type semiconductor properties and provide many more zigzag- and armchair-edges to facilitate control of the bandgap. B-GNRs are used for the photodegradation of Rhodamine B in order to demonstrate their excellent conductivity and photocatalytic activity.

Silver halide/silver iodide@silver composite with excellent visible light photocatalytic activity for methyl orange degradation.

AgBr/AgI@Ag composite photocatalyst was prepared by a handy multistep route, including controllable double-jet precipitation to synthesize cubic AgBr microcrystals, ion exchange to form AgI on AgBr surface, and visible light reduction to generate Ag nanoparticles. UV-Vis diffuse reflectance and electrochemical impedance spectra demonstrated that AgBr/AgI composite structure not only favors forming more silver nanoparticles to harvest visible light but also facilitates the transfer of charge carriers when compared with pure AgBr. Beneficial from the synergistic effect of highly effective visible light harvest and electron-hole separation, AgBr/AgI@Ag shows higher photocatalytic activity for the degradation of methyl orange (MO) than AgBr, AgBr@Ag, and AgBr/AgBr.

CeO2 mediated photocatalytic degradation studies of C.I. acid orange 7.

CeO2 nanoparticles were prepared by a simple precipitation method, followed by calcination treatment. By selecting photocatalytic degradation of acid orange 7 (AO7) as a probe reaction, the influences of calcination temperature of catalyst, the concentration of AO7, initial pH value of AO7 solution and catalyst dosage on the photocatalytic activity of CeO2 were studied. It was found that CeO2 calcined at 550 degrees C shows the highest photocatalytic activity under visible light irradiation.

Microemulsion-mediated solvothermal synthesis and photocatalytic properties of crystalline titania with controllable phases of anatase and rutile.

Titanium oxide with different ratios of anatase to rutile has been prepared by the microemulsion-mediated solvothermal method. The resulting samples were investigated by X-ray diffraction, Raman spectroscopy, scanning electron microscopy, UV-vis diffuse reflectance spectra, transmission electron microscopy and Brunauer-Emmett-Teller analysis. The contents of anatase and rutile in the TiO(2) particles have been successfully controlled by simply adjusting the amount of urea in the aqueous phase of the microemulsion.

An economic method to prepare vacuum activated photocatalysts with high photo-activities and photosensitivities.

This study reports a simple and economic method to modify Degussa P25 with a vacuum activated procedure, resulting in its high photo-activity and photosensitivity, which suggests this method to be a starting point for the extension of its application to photocatalysis.

Synthesis and characterization of thermally stable Sm,N co-doped TiO2 with highly visible light activity.

Samarium and nitrogen co-doped titania (Sm/N-TiO(2)) was successfully prepared via coprecipitation method. The resulting materials were characterized by X-ray diffraction (XRD), N(2) physical adsorption, UV-vis absorbance spectroscopy, X-ray photoelectron spectroscopy (XPS), high-resolution transmission electron microscopy (HRTEM) and Fourier transform infrared (FTIR) spectra. Experimental results indicated that samarium doping inhibited the growth of crystalline size and the transformation from anatase to rutile phase.

Thermally stable SiO2-doped mesoporous anatase TiO2 with large surface area and excellent photocatalytic activity.

A thermally stable SiO(2)-doped mesoporous TiO(2) with high crystallinity was prepared by a templating method. The content of SiO(2) dopant was varied from 3% to 20%. The gels were characterized by TG-DTA analysis.

Comparative studies of operational parameters of degradation of azo dyes in visible light by highly efficient WOx/TiO2 photocatalyst.

The multidimensional aspects of the photocatalytic activity were investigated in a systematic way by employing the dyes Acid Orange 7 (AO7) and Methyl Orange (MO) as substrates in terms of their degradation or conversion rates. 4.0% WO(x)/TiO(2) nanocomposite demonstrated the best reactivity under visible light, allowing more efficient usage of solar light.

Preparation of Fe3+-doped TiO2 catalysts by controlled hydrolysis of titanium alkoxide and study on their photocatalytic activity for methyl orange degradation.

Fe3+-doped TiO2 (Fe-TiO2) porous microspheres were prepared by controlled hydrolysis of Ti(OC4H9)4 with water generated "in situ" via an esterification reaction between acetic acid and ethanol, followed by hydrothermal treatment. The samples were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), atomic absorption flame emission spectroscopy (AAS), electron paramagnetic resonance (EPR) spectrum, X-ray photoelectron spectroscopy (XPS), UV-vis diffuse reflectance spectroscopy (DRS), and nitrogen adsorption-desorption methods. All of the undoped TiO2 and Fe-TiO2 samples exclusively consist of primary anatase crystallites, which further form porous microspheres with diameters ranging from 150 to 500 nm.

Preparation of Ce-TiO2 catalysts by controlled hydrolysis of titanium alkoxide based on esterification reaction and study on its photocatalytic activity.

The Ce-TiO2 catalysts were prepared by controlled hydrolysis of Ti(OC(4)H(9))(4) with water generated "in situ" via an esterification reaction between acetic acid and ethanol, followed by hydrothermal treatment. The samples were characterized by X-ray diffraction (XRD), UV-vis diffuse reflectance spectroscopy (DRS), scanning electron microscopy (SEM), atomic absorption flame emission spectroscopy (AAS), and nitrogen adsorption-desorption methods. Both of undoped TiO2 and Ce-TiO2 samples exclusively consist of primary anatase crystallites, which further form spherical aggregates with diameters ranging from 100 to 500 nm.

Influences of acids and salts on the crystalline phase and morphology of TiO2 prepared under ultrasound irradiation.

Nanocrystalline TiO2 powders were rapidly prepared by hydrolysis of Ti(OC4H9)4 under ultrasound irradiation. The influences of acids (HCl, HNO3, and H2SO4) and their corresponding salts (NaCl, KNO3, and Na2SO4) on the crystalline phase and morphology of products were investigated, respectively. Compared with NaCl and KNO3 that show no evident influence on the crystalline phase, HCl and HNO3 have a decisive influence on the crystalline phase of the products.