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Scheelite-type surfactant-assisted SrWO4 was prepared via a simple co-precipitation method. The effect of various surfactants such as hexamethylenetetramine, polyvinylpyrrolidone, and sodium dodecyl sulphate, on the structural, morphological and photoluminescence (PL) properties of SrWO4 was investigated. Powder X-ray diffraction and the Rietveld profile refinement technique confirmed the tetragonal structure of all the as-synthesized SrWO4 materials. Among the three surfactants, particles with spherical morphology were observed for SDS-assisted SrWO4. Surfactant-assisted SrWO4 exhibited bluish-green emission around 500 nm, ascribed to the presence of WO 4 2 - luminescence centre at 284 nm excitation, and the PL emission intensity significantly increased in the presence of surfactant. Electron density distribution analysis of a single unit cell for all the prepared materials was investigated, and correlated with the PL results. [ABSTRACT FROM AUTHOR]

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]

The movement of the sulfur species of a lithium – sulfur battery cathode was directly observed through pioneering operando SAXS analysis. Micropore is a prior repository for sulfur before and after the electrochemical reaction. Mesopore is actual reaction site for sulfur species. The separate properties of the pores were established, adding critical insight to advanced carbon cathode material design. [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]