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With the rapid growth of secondary batteries used in various industries, methods for analyzing battery elements such as electrodes and electrolytes have also improved. In addition, as the utility of nano‐scaled electrode materials have attracted greater attention, it has become increasingly clear that conventional electrochemical analytic methods have limitations. Consequently, electron microscopy and even synchrotron x‐ray radiation techniques have been adopted and are now widely used. Among several advanced analytical techniques, synchrotron radiation‐based operando small‐angle x‐ray scattering (SAXS) enables real‐time analysis of changes in the ordering of nanostructures and in the electron densities of electrodes and solid electrolytes during electrochemical reactions. In this review, the principle and applications of operando SAXS are briefly introduced, to help in understanding the complex nanostructural behaviors of battery components used in secondary batteries, and furthermore, it is hoped to contribute to innovative materials design. [ABSTRACT FROM AUTHOR]

Abstract: Mesoporous silica KIT-6-, SBA-15-, and MCM-41-supported Ni catalysts (Ni/KIT-6, Ni/SBA-15, and Ni/MCM-41) were prepared via impregnation method and studied for CO2 reforming of CH4. The catalysts were characterized by X-ray diffraction analysis, N2 physisorption measurements, scanning electron microscopy, transmission electron microscopy, and temperature-programmed oxidation (O2-TPO). The Ni/KIT-6 catalyst exhibited higher catalytic activity and long-term stability compared with Ni/SBA-15 or Ni/MCM-41. The conversion of CH4 and CO2 over Ni/KIT-6 was 99 and 99 %, respectively. The superior catalytic behavior of Ni/KIT-6 is closely related to the large-pore cubic Ia3d structure of KIT-6, which enhanced dispersion of Ni nanoparticles, reduced carbon deposition, and increased diffusion of reactant and products.Graphical Abstract: [ABSTRACT FROM AUTHOR]

Presents a general approach for the direct determination of three-dimensional mesoporous structures by electron microscopy. How mesostructured composite materials are obtained; Interest in three-dimensional mesopourous materials obtained by removing the organic phase for applications such as catalysis and chemical sensing or separation; Reports on high-resolution details of cage and pore structures of periodically ordered mesoporous materials which reveal a highly ordered dual micro- and mesoscale pore structure.

Abstract: Mesoporous silica KIT-6-, SBA-15-, and MCM-41-supported Ni catalysts (Ni/KIT-6, Ni/SBA-15, and Ni/MCM-41) were prepared via impregnation method and studied for CO2 reforming of CH4. The catalysts were characterized by X-ray diffraction analysis, N2 physisorption measurements, scanning electron microscopy, transmission electron microscopy, and temperature-programmed oxidation (O2-TPO). The Ni/KIT-6 catalyst exhibited higher catalytic activity and long-term stability compared with Ni/SBA-15 or Ni/MCM-41. The conversion of CH4 and CO2 over Ni/KIT-6 was 99 and 99 %, respectively. The superior catalytic behavior of Ni/KIT-6 is closely related to the large-pore cubic Ia3d structure of KIT-6, which enhanced dispersion of Ni nanoparticles, reduced carbon deposition, and increased diffusion of reactant and products.Graphical Abstract: [ABSTRACT FROM AUTHOR]

• Highly ordered mesoporous WOx/SnO2 catalysts have been applied to the glycerol acetalization reaction. • Mesoporous WOx/SnO2 catalysts exhibited excellent catalytic performance in batch-type and continuous flow-type processes for catalytic synthesis of solketal from glycerol. • In a batch type process, 100% glycerol conversion and a solketal yield of 97.4% were achieved. Highly ordered WO x /mesoporous SnO 2 (WO x /meso‑SnO 2) catalysts with varying WO x loadings of (5 ∼ 20) wt% displaying excellent catalytic performance were demonstrated in the acetalization of glycerol with acetone. The synthesized catalysts were analyzed using various techniques including X-ray diffraction, N 2 -isotherm, electron microscopy, H 2 temperature programmed reduction, raman spectroscopy, and thermogravimetric analysis. For the acetalization of glycerol with acetone, the most active catalyst was found to be WO x /meso‑SnO 2 with 20 wt% WO x , and the maximum conversion of glycerol (100%) was obtained after 2 h at 20 °C, providing 97.4% selectivity (97.4% yield) for the five-membered product (solketal), due to the presence of a large number of acidic sites on the surface of the catalyst. The catalytic activity of 20 wt% WO x /meso‑SnO 2 was also studied in a flow reactor. Tests were carried out at 30 °C, acetone/glycerol=30, WHSV=(4 or 8) h −1, and atmospheric pressure for 24 h. The catalytic results showed that, when the WHSV was 4 h −1, after 24 h of time-on-stream, both the glycerol conversion of (100 to 97.9)% and solketal yield of (97.5 to 93.6)% slightly decreased. This result suggests the potential of the 20 wt% WO x /meso‑SnO 2 catalyst for the industrial acetalization of glycerol. [Display omitted] [ABSTRACT FROM AUTHOR]

Abstract: A new approach for the synthesis of Co–Fe Prussian blue nanoparticles with controlled size has been developed in the present work. Mixture of formamide and water was used as a reaction medium for the chemical synthesis of the nanoparticles at room temperature. It has been found that the size of nanoparticles can be controlled by varying the volume ratios between formamide and water. Powder X-ray diffraction, transmission electron microscopy, diffuse reflectance UV–vis absorption spectra, and nitrogen adsorption/desorption isotherms were employed to characterize the products. The optical properties of the nanoparticles depending on particle size were observed. [Copyright &y& Elsevier]