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Homogeneously Eu3+ doped LaOCl single crystals are firstly synthesized in a molten KCl-LiCl flux, and the well-shaped LaOCl:Eu3+ polyhedral micro-plates exhibit noticeable luminescent properties. The bulk LaOCl:Eu3+ micro-plate with a width of 1.03 μm and 1.37 μm in length shows a single crystal characteristic with the crystal face orientation of [00 1 ‾ ]. Both XRD patterns and EDS mapping indicate that the Eu3+ ions have been homogeneously doped into LaOCl lattice. LaOCl:Eu3+ nucleuses generated in molten KCl-LiCl flux at even 350 °C benefited to the decomposition of La(OH) 3 :Eu3+ precursor, and polyhedral LaOCl micro-plate is easily formed in molten KCl-LiCl salt due to the solid-ionic reaction and crystal growth. The luminescent properties of LaOCl:Eu3+ are firstly enhanced and then weakened with the increasing concentration of the doped Eu3+, 6% Eu3+ doped LaOCl:Eu3+ exhibits the best luminescent properties which can be used as a potential LED material. [ABSTRACT FROM AUTHOR]

Nanoceria was synthesized by treating cerium carbonate hydrate in a molten KOH-NaOH mixture at 200 °C. The nanoceria thus synthesized under a hydrogen atmosphere had a crystal size of 21.6 nm measured by XRD, consistent with the particle size of 23 nm measured by TEM. Raman spectra results indicated that the nanoceria produced under hydrogen had a downshift of 0.9 cm −1 from the sample synthesized in air. XPS spectra showed that the Ce 3+ fraction of the nanoceria synthesized in hydrogen was greater than that produced in air. The oxygen vacancies were formed by partial oxidization of the precursor in molten KOH-NaOH mixture. The UV–visible absorption properties of ceria synthesized under hydrogen showed a 34 nm red-shift compared with that synthesized in air. The nanoceria prepared in this work had a better catalytic property for CO oxidization than the commercial nanoceria. Results indicated that the increased Ce 3+ fraction or oxygen vacancies formed by this partial oxidization process extended the absorption edge of ceria resulting in a narrower band gap, and enhanced the catalytic activity of nanoceria. This method has proven to provide a simple and scalable method for the synthesis of high quality nanoceria. [ABSTRACT FROM AUTHOR]

Abstract: A series of zinc titanate nanoparticles was successfully synthesized using a simple sol–gel technique. The composites were characterized by thermogravimetric and differential thermal analysis (TG-DTA), X-ray diffraction (XRD) patterns, scanning electron microscope (SEM), X-ray photoelectron spectra (XPS) and UV–vis diffuse reflectance spectra (UV–vis). The photocatalytic activity of samples was investigated by degradation of humic acid (HA) in water under xenon lamp. The sample calcined at 800°C was found to exhibit much higher photocatalytic activity than the other samples. The investigation of photocatalytic mechanism indicates that the holes (h+) and ls may be the major reactive species for the degradation of HA. Meanwhile, the processing parameters such as the light source and the dosage of catalysts play an important role in tuning the photocatalytic activity. The enhancement of photocatalytic activity for the zinc titanate nanoparticles calcined at 800°C may be attributed to the higher redox ability, coordination of Ti ions and smaller particle size. [Copyright &y& Elsevier]

A ternary photocatalyst of LaOCl/CeO 2 -g-C 3 N 4 was designed and firstly synthesized by a facile KCl–LiCl molten salt method. The 60 %LaOCl/40 %CeO 2 -g-C 3 N 4 with a 6: 4 weight ratio of LaOCl to CeO 2 has an optimal degradation ratio (nearly 100%) for methylene blue (MB) with an impressive cyclic stability. Both of adsorption and photodegradation contribute to the high MB removal ratio, and kinetic study results show that the rate constant of photocatalytic degradation route is 0.0174 min−1, which is less than that of adsorption process (2.4406 min−1). The excellent adsorption performance of 60 %LaOCl/40 %CeO 2 -g-C 3 N 4 is attributed to its negative zeta potential (−35.40 mV) and larger average pore size. The photochemical characterizations suggest that the 60 %LaOCl/40 %CeO 2 -g-C 3 N 4 form a dual Z-scheme heterojunction, which enhances its separation efficiency of photogenerated e - / h + with an outstanding redox ability, and further promotes the photocatalytic activity. [Display omitted] • A ternary photocatalyst of 60 %LaOCl/40 %CeO 2 -g-C 3 N 4 was firstly synthesized by a KCl–LiCl molten salt mothed. • Negative zeta potential and suitable pore structure contribute to the superb adsorption ability of 60 %LaOCl/40 %CeO 2 -g-C 3 N 4. • 60 %LaOCl/40 %CeO 2 -g-C 3 N 4 shows a dual Z-scheme heterojunction which promotes its photocatalytic property. [ABSTRACT FROM AUTHOR]