YuLin Min

General Synthesis and Phase Control of Metal Molybdate Hydrates MMoO4·nH2O (M = Co, Ni, Mn, n = 0, 3/4, 1) Nano/Microcrystals by a Hydrothermal Approach: Magnetic, Photocatalytic, and Electrochemical Properties

Different phases and morphologies of molybdate hydrates MMoO 4. nH 2O (M = Co, Ni, Mn, n = 0, 3/4, 1) nano/microcrystals, which include NiMoO 4.H 2O microflowers, MnMoO 4.H 2O microparallelogram plates, and CoMoO 4.3/4H 2O microrods, can be selectively synthesized by a hydrothermal process. The pH and reaction temperature have a crucial influence on the synthesis and shape evolution of the final products. Uniform CoMoO 4.3/4H 2O and NiMoO 4.H 2O nanorod bundles can be produced by a hydrothermal process with the assistance of PEG-400. The calcination of CoMoO 4.3/4H 2O and NiMoO 4.H 2O at 500 and 550 degrees C, respectively, allows the formation of monoclinic beta-CoMoO 4 and alpha-NiMoO 4. The antiferromagnetic property of MnMoO 4.H 2O, MnMoO 4, and CoMoO 4.3/4H 2O has been studied for the first time. The photocatalytic activity of metal molybdate particles with different morphologies has been tested by degradation of acid fuchsine under visible light. Electrochemical performances of MMoO 4 (M = Ni, Co) nanorod bundles and MnMoO 4 microrods have been evaluated.

Synthesis of silica/carbon-encapsulated core-shell spheres: templates for other unique core-shell structures and applications in in situ loading of noble-metal nanoparticles.

Silica@carbon core-shell spheres have been synthesized via a hydrothermal carbonization procedure with glucose as the carbon precursor and silica spheres as the cores. Such SiO(2)@C core-shell spheres can be further used as templates to produce SiO(2)@C@SiO(2), and SiO(2)@SiO(2) spheres with a vacant region in two SiO(2) shells, noble-metal nanoparticle loaded SiO(2)@C core-shell spheres, and hollow carbon capsules through different follow-up processes. The obtained core-shell materials possess remarkable chemical reactivity in reducing noble-metal ions to nanoparticles, e.g., platinum. These unique core-shell spherical composites could find applications in catalyst supports, adsorbents, encapsulation, nanoreactors, and reaction templates.

Sonodegradation and photodegradation of methyl orange by InVO4/TiO2 nanojunction composites under ultrasonic and visible light irradiation

The InVO(4)/TiO(2) nanojunction composites with different weight ratio of 1:10, 1:25, 1:50 and 1:100 were successfully constructed using an ion impregnate method, followed by calcining temperature 400°C for 2h in Ar. The sono- and photo-catalytic activities of the InVO(4)/TiO(2) nanojunction composites were evaluated through the degradation of methyl orange (MO) in aqueous solution under ultrasonic and visible light irradiation, respectively. The experimental results determined that the (1:50) InVO(4)/TiO(2) nanojunction composite has exhibited the highest sonocatalytic activity. It can be ascribed to vectorial charge transfer at the co-excited InVO(4)/TiO(2) interface under ultrasonic irradiation, results in the complete separation of electrons and holes. Interestingly, the (1:25) InVO(4)/TiO(2) nanojunction composite displayed superior photocatalytic activity for MO degradation under visible light, indicating that InVO(4) as a narrow band gap sensitizer can expand photocatalytic activity of TiO(2) to visible region, and the charge transfer can be formed from high energy level of InVO(4) conduction band to the low energy level of TiO(2) conduction band in a present of excited InVO(4) alone under visible light irradiation. The sono- and photo-catalytic activities of the InVO(4)/TiO(2) nanojunction composites were found to be dependent significantly on different InVO(4) contents, which can be explained by the influence of charge transfer on the basis of the work functions of different catalysis mechanism.

The synthesis of poly(p-phenylenediamine) microstructures without oxidant and their effective adsorption of lead ions

In this paper, we report a novel method for the shape-controlled synthesis of poly(p-phenylenediamine) (PpPD) polymer microstructures using a UV lamp as the oxidation energy source and poly(N-vinylpyrrolidone) (PVP) as the surfactant. By adjusting the synthetic conditions, a series of well-defined and uniform PpPD microstructures have been successfully prepared. The results demonstrate that although PVP plays an important role in controlling the morphology of such polymer particles, it has no influence on the intrinsic polymer structures. The as-obtained PpPD polymer microstructures show excellent adsorption ability in the removal of lead ions, which might be very useful in many practical applications, including water purification and waste treatment.

Morphology-controllable synthesis of CuO micro-shuttles for photocatalytic activity

In this article, morphology-controllable synthesis of CuO micro-shuttles has been achieved by a solvothermal process in a mixed solvent of water and ethanol. Uniform CuO crystals with novel structures can be fabricated by tuning the volume ratio of water and ethanol. The as-synthesized samples were characterized by the X-ray powder diffraction, scanning electron microscopy and transmission electron microscopy. The photocatalytic activities of the products were examined by measuring the photodegradation of methyl orange solution under ultraviolet radiation. The results show that the as-synthesized products display an excellent photocatalytic activity, which may be aroused from their particular morphologies and specific surface area.

The synthesis and characterization of Zn–Tryptophan complexes and their luminescence properties

In this paper, flake-like Zn–Tryptophan complexes were successfully synthesized by a refluxing method. We confirm that the reaction time influences Zn–Tryptophan complexes growth during the whole process. The intensity of the peaks of Zn–Tryptophan in photoluminescence spectrum increased twice or more compared with that of pure Tryptophan. This synthesis approach is expected to become an appropriate method for preparation of other M-organism complexes.

Simple method to synthesize novel mesoporous zinc oxide

Mesoporous ZnO microfans have been successfully synthesized from the ZnS microfans by the thermal treatment. The morphology, specific surface area, and optical properties of ZnO microfans were analyzed by X-ray diffraction, scanning electron microscope, N2 adsorption,and photoluminescence spectroscopy. Results reveal that ZnO microfans show good crystalline quality, high specific surface area, and excellent optical properties.