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Solid-state process of introducing oxygen vacancies into the structure of TiO2 and ZnO particles was studied. The phase transformations of metal oxides throughout the process were examined by X-ray diffraction (XRD). The influence of the loaded mechanical stress on the band gap was studied by diffuse reflectance spectroscopy (DRS). Mechanism of elimination of oxygen atoms from the surface of the oxides by co-milling with polyolefins, which can lead to creation of more effective materials for waste water treatment, was proposed.

Solid-state process of introducing oxygen vacancies into the structure of TiO2 and ZnO particles was studied. The phase transformations of metal oxides throughout the process were examined by X-ray diffraction (XRD). The influence of the loaded mechanical stress on the band gap was studied by diffuse reflectance spectroscopy (DRS). Mechanism of elimination of oxygen atoms from the surface of the oxides by co-milling with polyolefins, which can lead to creation of more effective materials for waste water treatment, was proposed.

The present poster contribution aims at optimization of electrochemical properties of titania (N doped anatase TiO2 / N) and Li-Ti ternary oxides (Li4Ti5O12, LTO) with respect to their performance as anode materials in Li-ion battery by using mechanochemical effects.

The present poster contribution aims at optimization of electrochemical properties of titania (N doped anatase TiO2 / N) and Li-Ti ternary oxides (Li4Ti5O12, LTO) with respect to their performance as anode materials in Li-ion battery by using mechanochemical effects.

The present poster contribution aims at optimization of electrochemical properties of titania (N doped anatase TiO2 / N) and Li-Ti ternary oxides (Li4Ti5O12, LTO) with respect to their performance as anode materials in Li-ion battery by using mechanochemical effects.

The present poster contribution aims at optimization of electrochemical properties of titania (N doped anatase TiO2 / N) and Li-Ti ternary oxides (Li4Ti5O12, LTO) with respect to their performance as anode materials in Li-ion battery by using mechanochemical effects.

Changes in the colloid-chemical and photocatalytic properties of titania nanoparticles by attrition milling in the presence of glycine (Gly) and subsequent heat treatment were examined. By milling at 1500 rpm for 6 h, the average particle size was decreased from 123 to 85 nm, with simultaneous decrease in the specific surface area from 35.1 to 23.5 m2/g. Interfacial reactions between titania and Gly were confirmed by Fourier transform infrared spectroscopy, from the blue shift of the COO− related vibrational bands by 25 cm−1, relative to the same band from the pristine Gly. The bimodal N1s x-ray photoelectron spectroscopy peak similar to that from the reported titania—amino acid complex is another indication of the complex formation with the participation of nitrogen. When the dispersion was dried and calcined at 500 °C in air, the powder exhibited pale yellow color. Diffuse reflectance spectroscopy showed significant visible light absorption, suggesting nitrogen incorporation into titania. The fired product showed high photocatalytic antibacterial activity by irradiation of blue light centered at around 440 nm, using Escherichia coli as a specimen of bacterial species. Thus, the present Gly-modified titania nanoparticles could be used for eliminating indoor bacteria under soft blue illumination. The series of interfacial chemical processes involved are also discussed

Mechanical activation can be regarded as a multi-step process with changes in the energetic parameters and the amount of accumulated energy of solids in each step. Here we report the influence of mechanochemical processing on the synthesis of LiFePO4 powders. The different precursor powders were milled in a planetary mill by using WC vials and 5 mm balls made of the same material. A slightly reductive atmosphere (Ar + 5%H2) was used in both mechanical stressing and thermal annealing so as to prevent the oxidation of iron. All synthesis steps were followed by an X-ray diffractometry and FT-IR spectroscopy. The results were compared with previous findings of precipitated and annealed powder, without mechanochemical treatment.

Mechanical activation can be regarded as a multi-step process with changes in the energetic parameters and the amount of accumulated energy of solids in each step. Here we report the influence of mechanochemical processing on the synthesis of LiFePO4 powders. The different precursor powders were milled in a planetary mill by using WC vials and 5 mm balls made of the same material. A slightly reductive atmosphere (Ar + 5%H2) was used in both mechanical stressing and thermal annealing so as to prevent the oxidation of iron. All synthesis steps were followed by an X-ray diffractometry and FT-IR spectroscopy. The results were compared with previous findings of precipitated and annealed powder, without mechanochemical treatment.

Mechanical activation can be regarded as a multi-step process with changes in the energetic parameters and the amount of accumulated energy of solids in each step. Here we report the influence of mechanochemical processing on the synthesis of LiFePO4 powders. The different precursor powders were milled in a planetary mill by using WC vials and 5 mm balls made of the same material. A slightly reductive atmosphere (Ar + 5%H2) was used in both mechanical stressing and thermal annealing so as to prevent the oxidation of iron. All synthesis steps were followed by an X-ray diffractometry and FT-IR spectroscopy. The results were compared with previous findings of precipitated and annealed powder, without mechanochemical treatment.

Mechanical activation can be regarded as a multi-step process with changes in the energetic parameters and the amount of accumulated energy of solids in each step. Here we report the influence of mechanochemical processing on the synthesis of LiFePO4 powders. The different precursor powders were milled in a planetary mill by using WC vials and 5 mm balls made of the same material. A slightly reductive atmosphere (Ar + 5%H2) was used in both mechanical stressing and thermal annealing so as to prevent the oxidation of iron. All synthesis steps were followed by an X-ray diffractometry and FT-IR spectroscopy. The results were compared with previous findings of precipitated and annealed powder, without mechanochemical treatment.

Roles of various organic crystals (OC), notably those containing nitrogen, on the preparation and properties of source materials for electroceramics are featured from the author’s own experimental studies. When OC are intimately mixed with metal salts like carbonates, their decomposition is accelerated, liberating the diffusing species at temperatures lower than usual. Mixing of OC with metal oxides under mechanical stressing results in anion exchange and eases diffusion of guest species. Case studies on 3 categories, i.e. i) substitution of oxygen in titania with nitrogen and introduction of oxygen vacancies during co-grinding titania with urea, glycine and/or polytetra fluoroethylene; ii) increase in the rate of reaction of barium titanate formation via a solid state route by OCs with detailed process analysis with glycine as an example of OC, and iii) phase pure solid state synthesis of Li4Ti5O12 by mechanically activating the intermediate, Li2TiO3 with 3 amino acids as OCs.

publisher, 横浜, Matastable phase of iron (III) oxide, γ-Fe2O3, transforms to the stable phase, α-Fe2O3, by either isothermal wet ball-milling or vacuum hot-pressing. From kinetic analysis of these processes, it was found that application of external force makes an alternative mechanism of the transformation operative. Decrease in the activation energy with increasing applied external force suggests that mechanical force elevates the potential energy of the reactant particles by enhancing strains or defects in the crystal. Comparing the results to those on the mechanochemical transformation of PbO, reported previously by the authors, reveals that mechanical force acts on the polymorphic transformation at least by two different ways depending on the nature of the material, although the mechanism of transmission of the external force to the particles remains almost unchanged irrespective of the material.

Changes in the colloid-chemical and photocatalytic properties of titania nanoparticles by attrition milling in the presence of glycine (Gly) and subsequent heat treatment were examined. By milling at 1500 rpm for 6 h, the average particle size was decreased from 123 to 85 nm, with simultaneous decrease in the specific surface area from 35.1 to 23.5 m2/g. Interfacial reactions between titania and Gly were confirmed by Fourier transform infrared spectroscopy, from the blue shift of the COO− related vibrational bands by 25 cm−1, relative to the same band from the pristine Gly. The bimodal N1s x-ray photoelectron spectroscopy peak similar to that from the reported titania—amino acid complex is another indication of the complex formation with the participation of nitrogen. When the dispersion was dried and calcined at 500 °C in air, the powder exhibited pale yellow color. Diffuse reflectance spectroscopy showed significant visible light absorption, suggesting nitrogen incorporation into titania. The fired product showed high photocatalytic antibacterial activity by irradiation of blue light centered at around 440 nm, using Escherichia coli as a specimen of bacterial species. Thus, the present Gly-modified titania nanoparticles could be used for eliminating indoor bacteria under soft blue illumination. The series of interfacial chemical processes involved are also discussed