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Magnesium titanates (including three main phases, Mg 2 TiO 4 , MgTiO 3 and MgTi 2 O 5 ) and Mn 4+ doped magnesium titanates were successfully prepared in a simple route. Mn 4+ occupied octahedral positions to substitute Ti 4+ in the magnesium titanates host lattice. The absorption bands at 400–600 nm assigned to the d-d band transition of Mn 4+ had difference in three systems, which were strongly influenced by local crystal field environments. In this work, the samples doped Mn 4+ showed the difference in emission peak positions, attributing to the 2 E g → 4 A 2g emission process of Mn 4+ . Crystal field strength of host material and Mn O nephelauxetic nature of the Mn 4+ -doped magnesium titanates (Mg 2 TiO 4 :Mn 4+ , MgTiO 3 :Mn 4+ and MgTi 2 O 5 :Mn 4+ ) influenced on the photoluminescent properties, which was demonstrated through the combination with density functional theory (DFT) and experimental method. These results suggested that Mn 4+ doped Mg 2 TiO 4 material had high color purity, which was a promising material for red phosphor in attractive white-light LEDs application. This research is very useful because it could rapidly predicted the luminescent property of new Mn 4+ doped materials through DFT calculation. [ABSTRACT FROM AUTHOR]

To improve the interfacial microstructure and mechanical behaviors of Sn-58Bi/Cu joint, minor Zn element was alloyed into Cu substrate. The interfacial intermetallic compound (IMC) growth and bending properties of Sn-58Bi/Cu and Sn-58Bi/Cu-2.29Zn were studied with the effect of isothermal liquid and solid aging. Although there was no significant change on the composition, thickness and morphology of interfacial IMC under liquid aging, the depressing of IMC growth at the interface between Sn-58Bi solder and substrate and the avoidance on formation of Cu 3 Sn IMC, Kirkendall voids and Bi segregation at the IMC/Cu interface were realized with Cu-Zn substrate under isothermal solid aging. Joint strength and fracture behavior were also improved by Cu-Zn substrate. There was no obvious decreasing on the joint strength and the fracture during bending was mainly occurred in the solder matrix with ductile fracture mode or along the solder/IMC interface with partly brittle fracture mode for Cu-Zn joint compared with the dramatically decreasing on joint strength and brittle fracture mode occurred along the interface between IMC and Cu for Sn-Bi/Cu joints after aging. [ABSTRACT FROM AUTHOR]

The CO 2 photocatalytic reduction is an essential strategy to meet with the carbon-neutral cycle. This investigation presents the successful preparation of a CuBi 2 O 4 /Bi 12 O 17 Cl 2 (CuBO/UBOCl) composite for CO 2 photocatalytic reduction, forming a series S-type heterostructures where CuBO rectangle plates tile on UBOCl nano-belts. The optimal CuBO/UBOCl-50 % achieved significant CO 2 reduction to CO (231.84 μmol·g−1) within 3 hours of simulated sunlight irradiation, with dramatically improved stability. Mechanistically, CuBO's narrowed band gap enables efficient solar energy absorption, while UBOCl's abundant anion defects facilitate CO 2 trapping, enhancing photocatalytic performance. Furthermore, the formation of a S-type heterostructure can best separate photo-carriers and maintain strong redox capacity. In conclusion, this investigation proposes a novel approach for developing solar-driven photocatalysts for effective CO 2 conversion. • A S-type heterostructure photocatalyst was prepared with rectangle CuBi 2 O 4 tile on Bi 12 O 17 Cl 2 nanobelt. • CuBi 2 O 4 /Bi 12 O 17 Cl 2 reduce CO 2 to CO with a 77.28 μmol·g−1∙h−1 yield by 3 h sunlight irradiation. • A band narrowed CuBi 2 O 4 adsorbs solar energy and defects affluent Bi 12 O 17 Cl 2 traps CO 2. • CuBi 2 O 4 /Bi 12 O 17 Cl 2 array well separate electron-hole and maintain strong redox ability. • CuBi 2 O 4 /Bi 12 O 17 Cl 2 exhibits good stability, ascribed to the strong component's interaction. [ABSTRACT FROM AUTHOR]

Abstract The structures and hydrogen adsorption properties of {Cr 3 F(H 2 O) 2 O[(O 2 C)-C 6 H 4 -(CO 2)] 3 ・nH 2 O(n∼25)} (MIL-101) and its Pd composites have been investigated by X-ray diffraction (XRD) analysis, transmission electron microscope (TEM), X-ray photoelectron spectroscopy (XPS), and specific surface area tests (BET). The as-prepared Pd/MIL-101 composites were microporous and maintained three-dimensional topology of MIL-101 before and after Pd loading that existed in the skeleton. A carbon bridge was formed between Pd metal and MIL-101 to improve the hydrogen storage. The loaded Pd reduced the hydrogen absorption enthalpy of MIL-101, and thus improved the storage of hydrogen compared with MIL-101. The diffusion coefficient reached 7.233 × 10−9 in the Pd/MIL-101 nanocomposites. Highlights • The Pd/MIL-101 composite adsorbents were prepared. • The load of Pd reduced the enthalpy of hydride generation. • The load of Pd increased the diffusion coefficient and improved the hydrogen storage performance. [ABSTRACT FROM AUTHOR]

In this work, a series of Au-loaded Na 2 Ta 2 O 6 nanocomposite photocatalysts were prepared via a chemical reduction process. It was observed the tiny Au nanoparticles (∼5 nm) uniformly anchored on the surface of Na 2 Ta 2 O 6 nanoparticles with a well crystallized octahedral morphology. The as-prepared samples demonstrated high efficiency and good recyclability toward reduction of toxic nitrobenzenes to nontoxic aminobenzene. Significantly, a very quickly rate of 2666.7 min −1 g −1 under the simulated solar light irradiation was observed for nitrobenzenes (NB) derivatives reduction. It was found 4-nitrophenol can be completely converted to 4- aminobenzene in only 4 min, 2.35 times higher than that in dark. By evaluate activities over several representative support materials under different reaction conditions, a new photo-synergistic catalytic mechanism was proposed. In the thermocatalytic process, the surface plasmons resonance of Au nanoparticles excited by visible light, and the electron transfer from Na 2 Ta 2 O 6 semiconductor to Au nanoparticle assisted by ultraviolet light, all make the significantly contributions to achieve the efficient reduction of 4-nitrophenol under solar illumination. [ABSTRACT FROM AUTHOR]

Tetracyclines (TCs) are one of the most common types of antibiotics. In this investigation, a 2D–2D BiO 2−x /Bi 2 WO 6 composite has been assembled via growing Bi 2 WO 6 in situ on the sheets of BiO 2−x by a simple hydrothermal process and has been applied to removal residual TCs in waterbody. The XRD, SEM, TEM, and XPS analyses reveal that BiO 2−x /Bi 2 WO 6 composite is a compact 2D–2D heterojunction and exhibit rich oxygen vacancy. Among the series of composites with the different ratios, 20BiO 2−x /Bi 2 WO 6 displays a more excellent visible-light photocatalytic performance with a 96.4% degradation rate of TC, compared to pure Bi 2 WO 6 (47.9%) and BiO 2−x (73.3%). The enhanced photodegraded mechanism is revealed in view of the XPS analysis, ESR spectra and density function theory (DFT) calculation. The excellent photocatalytic performance is attributed to the BiO 2−x /Bi 2 WO 6 heterojunction and the generation of more oxygen vacancies originated from the co-shared Bi species and redox couple Bi5+/Bi3+ pairs in composite, which will increase the light trapping ability, accelerate the electron transfer, induce a strong redox, and lead to the excellent photo-degraded activity for aqueous TC. This research provides a new insight into the development of the novel bismuth base photocatalyst via growing in situ strategy in the application to photo-catalytically decompose aqueous antibiotic residues. [Display omitted] • A 2D–2D BiO 2−x /Bi 2 WO 6 composite was prepared via layer on layer oxidation. • BiO 2−x /Bi 2 WO 6 exhibits the excellent photo-degraded performance for TC. • The co-shared Bi species and redox couple Bi5+/Bi3+ pairs accelerate the electron transfer. • The more oxygen vacancies exist in BiO 2−x /Bi 2 WO 6 composite. [ABSTRACT FROM AUTHOR]

Tetracyclines (TCs) are one of the most common types of antibiotics. In this investigation, a 2D–2D BiO 2−x /Bi 2 WO 6 composite has been assembled via growing Bi 2 WO 6 in situ on the sheets of BiO 2−x by a simple hydrothermal process and has been applied to removal residual TCs in waterbody. The XRD, SEM, TEM, and XPS analyses reveal that BiO 2−x /Bi 2 WO 6 composite is a compact 2D–2D heterojunction and exhibit rich oxygen vacancy. Among the series of composites with the different ratios, 20BiO 2−x /Bi 2 WO 6 displays a more excellent visible-light photocatalytic performance with a 96.4% degradation rate of TC, compared to pure Bi 2 WO 6 (47.9%) and BiO 2−x (73.3%). The enhanced photodegraded mechanism is revealed in view of the XPS analysis, ESR spectra and density function theory (DFT) calculation. The excellent photocatalytic performance is attributed to the BiO 2−x /Bi 2 WO 6 heterojunction and the generation of more oxygen vacancies originated from the co-shared Bi species and redox couple Bi5+/Bi3+ pairs in composite, which will increase the light trapping ability, accelerate the electron transfer, induce a strong redox, and lead to the excellent photo-degraded activity for aqueous TC. This research provides a new insight into the development of the novel bismuth base photocatalyst via growing in situ strategy in the application to photo-catalytically decompose aqueous antibiotic residues. [Display omitted] • A 2D–2D BiO 2−x /Bi 2 WO 6 composite was prepared via layer on layer oxidation. • BiO 2−x /Bi 2 WO 6 exhibits the excellent photo-degraded performance for TC. • The co-shared Bi species and redox couple Bi5+/Bi3+ pairs accelerate the electron transfer. • The more oxygen vacancies exist in BiO 2−x /Bi 2 WO 6 composite. [ABSTRACT FROM AUTHOR]

In this study, a highly uniform ZnO/NaTaO 3 composite was prepared via simple hydrothermal synthesis. XRD confirmed the composite was constructed by pure cubic phase of NaTaO 3 and hexagonal phase of ZnO. SEM analysis showed that as-prepared ZnO/NaTaO 3 shaped as an irregular ginger with an obviously smaller size than that of pure ZnO without obvious agglomeration. EDS mapping demonstrated that the four elements (Na, Ta, O, Zn) in the composite were very uniformly distributed. The photocatalytic behaviors of as-prepared composites were studied in the degradation of methylene blue both under UV and visible irradiation. The bare ZnO showed the highest activity with 99.8% methylene blue (MB) photodegraded in 70 min under UV light irradiation whereas 94% photodegraded rate was achieved for ZnO/NaTaO 3 . More importantly, the uniform composite of ZnO/NaTaO 3 exhibited effective degradation of methylene blue under visible light which can be attributed to the well dyes adsorption abilities and the high efficiency of electron separation, induced by the synergistic effect between ZnO and NaTaO 3 . It is confirmed the dye rather than a semiconductor is excited under visible light irradiation and a self-sensitized photocatalytic mechanism was then proposed based on the experimental results. [ABSTRACT FROM AUTHOR]

Abstract: This work reports on the preparation of cellular-like Co3O4 nanocrystals with tailored physical properties via a seeded method by high temperature disposal. By increasing the disposal temperature, Co(OH)2 seeds can be efficiently transformed to Co3O4 nanocrystals. Systematic sample characterization using combined techniques of X-ray diffraction, scan electron microscope, Fourier transformed infrared spectra, UV–visible diffuse reflectance spectra, Barrett–Emmett–Teller technique and XPS spectra indicates that Co3O4 nanocrystals showed a monotonically lattice expansion with particle size reduction, which can be well-defined as a function of particle sizes as well as valence state of cobalt ions. As the consequence of lattice expansion of Co3O4 nanocrystals, the ν1 and ν2 modes of Co3O4 in infrared spectra showed systematic red shift from 580, 669 to 568, 663cm−1, respectively. Co3O4 nanocrystals prepared at 300°C displayed highest catalytic property for HCHO conversion, which can be explained by the balance of surface absorbed OH groups, BET surface area and charge state of cobalt ions. [Copyright &y& Elsevier]

Pt based catalysts with multi-component is widely used to improve the electrocatalytic ability in alcohol oxidation, however, it is still big challenge to maximize the synergies of different component. Herein, Pt/N-rGO/Nb 4 N 5 composites with multilayered structure were prepared, with nitrogen doped reduced graphene oxide (N-rGO) layer covered on Nb 4 N 5 sheet and Pt nanoparticles selective loaded on the interface of Nb 4 N 5 and N-rGO. Furthermore, N-rGO was confirmed to act as the connector between Pt and Nb 4 N 5 , ascribed to the Nb 4 N 5 –N-rGO-Pt bridge via N-doping of graphene and partial oxidation of Pt. By comparison, Pt/N-rGO/Nb 4 N 5 -10 composite showed the best distribution of N-doped rGO in the gap between Pt nanoparticles and Nb 4 Nb 5 sheet, as the ratio of urea and NbCl 5 was 10. Accordingly, Pt/N-rGO/Nb 4 N 5 -10 electrode exhibited the optimal catalytic activity and durability for multiple alcohol oxide in acid, such as methanol, ethanol, and ethylene glycol, since maximum ternary synergy was achieved by the stable multilayered structure, involving the highest ESCAs due to more exposed active sites of Pt nanoparticles, the best electrical conductivity ascribed to the incorporation of N-rGO, and excellent CO tolerance because of the efficient activation of water on Nb 4 N 5 and N-rGO. Pt/N-rGO/Nb 4 N 5 composite with multilayered structure and compact and stable interface between Pt, N-rGO layer and Nb 4 N 5 was provided with optimal ternary synergy, thus highly improving the catalytic activity and durability for multiple alcohol oxide in acid. Image 1 • The prepared Pt/N-rGO/Nb 4 N 5 composites showed multilayered structures. • N-rGO layer attached Pt nanoparticles to the surface of Nb 4 N 5. • Pt/N-rGO/Nb 4 N 5 composite exhibited optimal activity and durability in EOR. • The improved performance was due to the ternary synergy of Pt, Nb 4 N 5 and rGO. [ABSTRACT FROM AUTHOR]