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The development of efficient blue materials has been a continuous research topic in the field of organic light‐emitting diodes (OLEDs). In this paper, three aggregation‐induced emission enhancement active blue emitters, PIAnTPE, TPAAnTPE and CzAnTPE, are successfully synthesized by attaching a triphenylethylene unit and phenanthroimidazole/triphenylamine/carbazole moieties to the 9,10‐positions of anthracene, respectively. The three compounds exhibit good thermal stabilities, appropriate for the highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbital (LUMO) energy levels and display high photoluminescence quantum yields (PLQYs) of 65, 70 and 46 % in the solid state. Non‐doped blue devices using PIAnTPE, TPAAnTPE and CzAnTPE as the emitting layers show good electroluminescent performances, with the maximum external quantum efficiencies (EQEs) of 4.46, 4.13 and 4.04 %, respectively. More importantly, EQEs of all the three devices can be still retained when the luminescence reaches 1000 cd m−2, exhibiting quite small efficiency roll‐offs in the non‐doped OLEDs. Photoluminance: High‐efficiency blue emitters PIAnTPE, TPAAnTPE and CzAnTPE (see figure) are obtained and they exhibit EQEmax of 4.46, 4.13 and 4.04 %, respectively, in non‐doped OLEDs with low efficiency roll‐offs. [ABSTRACT FROM AUTHOR]

Abstract: Eu3+ doped SrAl2B2O7 phosphors were fabricated by the wet method. The structures of the phosphors were characterized by XRD. The doping content of Eu3+ ions in SrAl2B2O7:Eu3+ phosphors are 1%, 4%, 6%, 8%, 10% (molar fraction), respectively. Luminescence properties were analyzed by measuring the excitation and photoluminescence spectra. The luminescent properties of SrAl2B2O7:Eu3+ phosphors are discussed. It is shown that from 4% to 6% of doping content of Eu3+ ions under 392nm excitation in SrAl2B2O7:Eu3+ phosphors is optimum. [Copyright &y& Elsevier]

Abstract: In this study, the hydrothermal synthesized Fe3O4 nanoparticles are encapsulated with SiO2 via the Stöber method and further functionalized by the deposition of YVO4:Eu3+ phosphors, realizing a hybrid material with magnetic and luminescent properties. The bifunctional nanocomposites displayed a strong red emission and good ferrimagnetic behavior at room temperature. The high magnetization values make the nanocomposites quickly respond to the external magnetic field. The results also indicate that the nanocomposites may have potential applications for optical imaging or drug delivery. Moreover, we discussed the effects of the magnetic field on the luminescence intensity. [Copyright &y& Elsevier]

Abstract: Red-emitting Y2O3:Eu3+ and green-emitting Y2O3:Tb3+ and Y2O3:Eu3+, Tb3+ nanorods were synthesized by hydrothermal method. Their structure and micromorphology have been analyzed by X-ray powder diffraction (XRD) and transmission electron microscopy (TEM). The photoluminescence (PL) property of Y2O3:Eu3+,Tb3+ phosphor was investigated. In the same host (Y2O3), upon excitation with ultraviolet (UV) irradiation, it is shown that there are strong emissions at around 610 and 545nm corresponding to the forced electric dipole 5D0–7F2 transition of Eu3+ and 5D4–7F5 transition of Tb3+, respectively. Different qualities of Eu3+and Tb3+ ions are induced into the Y2O3 lattice. From the excitation spectrum, we speculate that there exists energy transfer from Tb3+ to Eu3+ ions .The emission color of powders reveals regular change in the separation of light emission. These powders can meet with the request of optical display material for different colors or can be potentially used as labels for biological molecules. [ABSTRACT FROM AUTHOR]

Abstract: By using metal nitrates as starting materials, SrAl2B2O7: Tb3+ and SrAl2B2O7: Ce3+, Tb3+ powder phosphors were prepared by sol–gel method. X-ray diffraction (XRD), photoluminescence excitation and emission, as well as kinetic decays were employed to characterize the resulting samples. The results show that energy transfers from Ce3+ to Tb3+ ions. The emission intensity of Tb3+ ions in SrAl2B2O7 could be greatly intensified when Ce3+ ions are doped into SrAl2B2O7: Tb3+. The decay times of SrAl2B2O7: Tb3+ were prolonged when Ce3+ ions were doped. The doping of Ce3+ ions not only improved the luminescent intensity, but also made the materials gets stable luminescent properties. [Copyright &y& Elsevier]

Acetylcholine (ACh), a neurotransmitter located in cholinergic synapses, can trigger cargo release from mesoporous silica nanoparticles equipped with calixarene- or pillarene-based nanovalves by removing macrocycles from the stalk components. The amount and speed of cargo release can be controlled by varying the concentration of ACh in solution or changing the type of gating macrocycle. Although this proof-of-concept study is far from a real-life application, it provides a possible route to treat diseases related to the central nervous system., (© 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)