Effect of sandwiched YbCllayer thickness on exciton dynamics of Ybdoped CsPbClperovskite photodetectors.

Ybdoped CsPbClmetal halide perovskite photodetectors (PDs) in the structure of CsPbCl(50 nm)/YbCl(nm)/CsPbCl(50 nm), in whichranges from 10 to 40 nm corresponding to the molar ratio from 6.3% to 25.2%, are fabricated by thermal evaporation on Si/SiOsubstrate.

Exciton dynamics and photoresponse behavior of theannealed CsSnBrperovskite films synthesized by thermal evaporation.

The CsSnBrphotodetectors are fabricated by thermal evaporation and 75 °Cannealing, and the effect ofannealing on the morphology, structure, exciton dynamics and photoresponse of thermally evaporated CsSnBrfilms are investigated. Especially, temperature dependent steady-state photoluminescence (PL) and transient PL decaying have been analyzed in details for understanding the exciton dynamics. Meanwhile, effect of annealing on the activation energy for trap sites (), exciton binding energy (), activation energy for interfacial trapped carriers (Δ), trap densities and carriers mobilities are studied and the annealed (A-CsSnBr) reveals obviously lowerand trap density together with notably higher carrier mobility than those of the unannealed (UA-CsSnBr).

Imidazo[1,2-]pyridazine as Building Blocks for Host Materials for High-Performance Red-Phosphorescent Organic Light-Emitting Devices.

A novel electron-transporting unit, imidazo [1,2-]pyridazine (IP), was first reported for developing host materials. The IP moiety possesses excellent electron-transporting ability and great thermal stability. Using carbazole as p-type units and IP as n-type units, several bipolar host materials, namely, IP6Cz, IP68Cz, IP36Cz, and IP368Cz, were developed through altering the substitution site of the IP core.

Effects of Au nanoparticles and ZnO morphology on the photocatalytic performance of Au doped ZnO/TiO films.

Au doped ZnO nanocomposite films on TiO seeding layer (AuZ/T) were fabricated by hydrothermal processing and their photocatalytic performance was investigated. It could be found that the AuZ/T with micrometer(μm)-sized, lying ZnO bulks revealed optimal photocatalytic performance toward methyl orange under simulated sunlight, whose apparent degradation rate constant K of 1.31 was about 20% higher compared to that of ZnO/TiO and 3 times higher compared to that of ZnO.

[1,2,4]Triazolo[1,5- a]pyridine-Based Host Materials for Green Phosphorescent and Delayed-Fluorescence OLEDs with Low Efficiency Roll-Off.

Herein, a series of universal bipolar host materials, 9,9'-([1,2,4]triazolo[1,5- a]pyridine-2,6-diylbis(4,1-phenylene))bis(9 H-carbazole) (TP26Cz1), 3-(2-(4-(9 H-carbazol-9-yl)phenyl)-[1,2,4]triazolo[1,5- a] pyridine-6-yl)-9-phenyl-9 H-carbazole (TP26Cz2), 9,9'-([1,2,4]triazolo[1,5- a]pyridine-2,7-diylbis(4,1-phenylene))bis(9 H-carbazole) (TP27Cz1), and 3-(2-(4-(9 H-carbazol-9-yl)phenyl)-[1,2,4]triazolo[1,5- a]pyridin-7-yl)-9-phenyl-9 H-carbazole (TP27Cz2), using [1,2,4]triazolo[1,5- a]pyridine (TP) as electron-transporting moiety and carbazole as hole-transporting moiety, were designed and synthesized. All four compounds possess remarkable carrier-transporting properties and excellent thermal stability with high glass-transition temperature ( T) in the range of 136-144 °C. The hole- and electron-transporting abilities could be regulated by adjusting the linkage mode between the carbazole and TP units, and balanced charge-transporting properties were realized in TP26Cz2 and TP27Cz2.

Photocatalytic Performance of 3D Ni/Graphene/ZnO Composites Fabricated by Hydrothermal Processing.

ZnO nanorods are fabricated by the hydrothermal processing on the 3 dimensional (3D) Ni/Chemical Vapor Deposition (CVD) grown multilayer graphene and 3D Ni foams, respectively, and their photocatalytic performance are investigated. It is found that the composites with the graphene sandwiched between the 3D Ni and ZnO nanorods with 4 hours hydrothermal growth exhibits superior photocatalytic performance toward methyl orange (MO) under simulated sunlight, whose apparent degradation rate constant is about 1.3 times larger compared to that without graphene incorporated.

[1,2,4]Triazolo[1,5-a]pyridine as Building Blocks for Universal Host Materials for High-Performance Red, Green, Blue and White Phosphorescent Organic Light-Emitting Devices.

The electron-accepting [1,2,4]triazolo[1,5-a]pyridine (TP) moiety was introduced to build bipolar host materials for the first time, and two host materials based on this TP acceptor and carbazole donor, namely, 9,9'-(2-([1,2,4]triazolo[1,5-a]pyridin-2-yl)-1,3-phenylene)bis(9H-carbazole) (o-CzTP) and 9,9'-(5-([1,2,4]triazolo[1,5-a]pyridin-2-yl)-1,3-phenylene)bis(9H-carbazole) (m-CzTP), were designed and synthesized. These two TP-based host materials possess a high triplet energy (>2.9 eV) and appropriate highest occupied molecular orbital/lowest unoccupied molecular orbital levels as well as the bipolar transporting feature, which permits their applicability as universal host materials in multicolor phosphorescent organic light-emitting devices (PhOLEDs).

Dependence of the Nitrogen Dioxide (NO₂) Sensitivity of SnO(x) -Sn/Graphene Gas Sensors on Vacuum Annealing and Ultraviolet (UV) Ozone Exposure.

Tin oxides and tin (SnO(x) -Sn) compound films were thermally evaporated onto chemical vapor deposition (CVD)-grown graphene films to obtain improved nitrogen dioxide (NO₂) gas sensitivity. The effects of the vacuum annealing and ultraviolet (UV) ozone (O₃) exposure of the bare graphene films prior to the thermal evaporation on the SnO(x) -Sn films’ sensitivities, bonding states, and surface morphologies were investigated. With increasing annealing time, the coverage of the SnO(x) -Sn nanoparticles on the graphene increased and the p to n sensitivity transition occurred when n-type SnO(x) -Sn nanoparticles became dominant instead of the p-type graphene films for sensors without O₃ exposure.