Achieving high power efficiencies at high-brightness levels is still an important issue for organic light-emitting diodes (OLEDs) based on the thermally activated delayed fluorescence (TADF) mechanism. Herein, enhanced electroluminescence efficiencies were achieved in fluorescent OLEDs using a TADF molecule, (4s,6s)-2,4,5,6-tetra(9H-carbazol-9-yl)isophthalonitrile (4CzIPN), as a host and quinacridone derivatives (QA) as fluorescent dopants.

No abstract

The development of scintillators is of fundamental and industrial meaning for their diverse applications. Despite the great advance in scintillating mono-crystals, challenge remains to search for novel scintillating materials with low cost, large volume, and high efficiency. Here, Tb 3+ -doped glass ceramics (GC) with crystallized Lu 6 O 5 F 8 nano-crystals were prepared and characterized as potential X-ray scintillators. Their structural, optical, and luminescent properties were explored systematically. After thermal treatment, X-ray excited luminescence (XEL) intensity from Lu 6 O 5 F 8 :Tb 3+ GC is greatly increased and the relative intensity is about 64% of commercial BGO scintillator, benefiting from preferential enrichment of Tb 3+ ions into Lu 6 O 5 F 8 nano-crystals with low phonon energy. Moreover, unusual decay behaviors of Tb 3+ emissions in GC sample are observed and discussed. Our results indicate that rare earth doped GC may offer a novel platform for designing and fabricating new scintillating materials in the future.

Tailed-Fe(2)O(3) ring arrays are fabricated by solution-dipping on a colloidal monolayer template. The influence of synthesis parameters on the quality of nanostructures has been investigated. The ring size can be controlled by changing the precursor concentration and varying the annealing time of the polystyrene sphere colloidal monolayer. In addition, the edge of the rings is sensitive to the surface tension of precursor solution, and high quality ordered ring arrays can be obtained by tuning the surface tension. This strategy allows the fabrication of specific metal oxides ring arrays with high quality and uniform morphology.

No abstract