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ZnO-NaSrBO3:Tb3+ (ZNT) composites were successfully synthesized via microwave-assisted reaction of the ZnO precursor with a NaSrBO3:Tb3+ suspension using a microwave synthesis system. The morphology, structure and photocatalytic performance in the degradation of methylene blue (MB) were characterized by scanning electron microscopy, transmission electron microscopy, X-ray diffraction, UV-vis absorption spectroscopy, fluorescence spectrophotometry and electrochemical impedance spectroscopy, respectively. The results show that the ZNT composites exhibit enhanced photocatalytic activity in the degradation of MB with a maximum degradation rate of 97% under visible light irradiation compared with pure ZnO (12%), which is ascribed to the increased light absorption and the reduction of photoelectron-hole pair recombination in ZnO with the introduction of NaSrBO3:Tb3+, as well as the light down-converting effect of NaSrBO3:Tb3+, which facilitates the self-sensitized degradation of MB. [ABSTRACT FROM AUTHOR]

Nitrogen-doped carbon microspheres (NCSs) were fabricated via a simple, fast and energy-saving microwave-assisted method followed by thermal treatment under an ammonia atmosphere. NCSs thermally treated at different temperatures were investigated as anode materials for lithium ion batteries (LIBs). The results show that NCSs treated at 900 °C exhibit a maximum reversible capacity of 816 mA h g-1 at a current density of 50 mA g-1 and preserve a capacity of 660 mA h g-1 after 50 cycles, and even at a high current density of 1000 mA g-1, a capacity of 255 mA h g-1 is maintained. The excellent electrochemical performance of NCSs is due to their porous structure and nitrogen-doping. The present NCSs should be promising low-cost anode materials with a high capacity and good cycle stability for LIBs. [ABSTRACT FROM AUTHOR]

Long afterglow Sr4Al14O25:Eu,Dy phosphors were introduced into the TiO2 photoanode of CdS quantum dot-sensitized solar cells (QDSSCs) as both a scattering and down converting layer, and the photovoltaic performances of the cells were investigated. The results show that the cell with Sr4Al14O25:Eu,Dy achieves a power conversion efficiency of 1.40%, which is an increase of 38% compared to the cell without Sr4Al14O25:Eu,Dy (1.02%). The performance improvement is attributed to enhanced light harvesting via improved light absorption and scattering processes. After a single sun illumination for 1 min and subsequent removal of the light source, the cell with Sr4Al14O25:Eu,Dy could be driven even in the dark by the long persistent light from Sr4Al14O25:Eu,Dy. [ABSTRACT FROM AUTHOR]

Mn2+ doped-AlN red phosphors were prepared by the solid-state reaction method. X-ray diffraction, SEM-EDS, photoluminescence and cathodoluminescence were utilized to characterize the prepared phosphor. Under UV light or electron beam excitation, the AlN:Mn2+ phosphors exhibit a strong red emission centered at 600 nm, which is ascribed to the characteristic 4T1(4G)–6A1(6S) transition of Mn2+. Energy level diagrams were constructed to discuss the photoluminescence and cathodoluminescence processes of the AlN:1% Mn2+ phosphor. The oxygen-related defects in AlN have great influence on the photoluminescence and cathodoluminescence properties of the AlN:1% Mn2+ phosphor. The dependence of brightness on accelerating voltage or electric current, the decay behavior of CL intensity under the electron bombardment, and the stability of CIE chromaticity coordinates were investigated in detail. The results indicate that the AlN:Mn2+ phosphor exhibits a higher brightness, higher color purity, and lower saturation compared to the red Y2O3:Eu3+ phosphor, which gives the AlN:Mn2+ phosphor great potential as a red phosphor for full color FEDs. [ABSTRACT FROM AUTHOR]

Reduced graphene (RG)-carbon nanotubes (CNTs) composite films are successfully fabricated by electrophoretic deposition and used as counter electrodes of dye-sensitized solar cells. RG is obtained by microwave-assisted reduction of graphite oxide dispersion in aqueous solution using a microwave synthesis system. By the optimization of CNTs content, photovoltaic conversion efficiency of the cell with RG-CNTs counter electrode reaches a maximum of 6.17% at one sun (AM 1.5 G, 100 mW cm−2) which is comparable to the cell with conventional Pt counter electrode. The results suggest that the RG-CNTs composite films provide a potential feasibility for replacing conventional Pt counter electrodes for DSSCs. [ABSTRACT FROM AUTHOR]

CdS–reduced graphene oxide (RGO) composites are successfully synthesized viathe microwave-assisted reduction of graphite oxide in a CdS precursor solution using a microwave synthesis system. The photocatalytic performances of CdS–RGO composites in the reduction of Cr(vi) are investigated. The results show that CdS–RGO composites exhibit enhanced photocatalytic performance for the reduction of Cr(vi) with a maximum removal rate of 92% under visible light irradiation as compared with pure CdS (79%) due to the increased light absorption intensity and the reduction of electron–hole pair recombination in CdS with the introduction of RGO. [ABSTRACT FROM AUTHOR]