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991.
Hole transporting material 5, 10, 15-tribenzyl-5H-diindolo[3, 2-a:3',2'-c]-carbazole for efficient optoelectronic applications as an active layer 下载免费PDF全文
In order to explore the novel application of the transparent hole-transporting material 5,10,15-tribenzyl-5Hdiindolo[3,2-a:3',2'-c]-carbazole(TBDI),in this article TBDI is used as an active layer but not a buffer layer in a photodetector(PD),organic light-emitting diode(OLED),and organic photovoltaic cell(OPV) for the first time.Firstly,the absorption and emission spectra of a blend layer comprised of TBDI and electron-transporting material bis-(2-methyl-8-quinolinate) 4-phenylphenolate(BAlq) are investigated.Based on the absorption properties,an organic PD with a peak absorption at 320 nm is fabricated,and a relatively-high detectivity of 2.44×10~(11) cm· Hz~(1/2)/W under 320-nm illumination is obtained.The TBDI/tris(8-hydroxyquinoline) aluminum(Alq_3) OLED device exhibits a comparable external quantum efficiency and current efficiency to a traditional 4,4-bis[N-(l-naphthyl)-N-phenyl-amino]biphenyl(α-NPD)/Alq_3 OLED.A C_(70)-based Schottky junction with 5 wt%-TBDI yields a power conversion efficiency of 5.0%,which is much higher than 1.7%for an α-NPD-based junction in the same configuration.These results suggest that TBDI has some promising properties which are in favor of the hole-transporting in Schottky junctions with a low-concentration donor. 相似文献
992.
993.
994.
基于标准CMOS工艺的p+源/漏区和n阱,设计了两种楔形瓣状结构的正向注入型硅基发光二极管(Si-LED),采用UMC 0.18μm 1P6M CMOS工艺设计制备.测试结果表明,正向注入型p+/n-well二极管的发射波长位于近红外波段,峰值波长在l 130 nm附近,且工作电压小于2V,与标准CMOS电路兼容.其中,八瓣结构的Si-LED (TS2)在200 mA时的发光功率可达1 200 nW,且未出现饱和,而注入电流为40 mA时的最大功率转换效率达5.8×10-6,约为四瓣结构器件(TSl)的2倍.所研制的Si-LED具有工作电压低、转换效率高等优点,有望在光互连领域得到应用. 相似文献
995.
《Current Applied Physics》2015,15(1):14-17
In this study, poly (linoleic acid)-g-poly(methyl methacrylate) (PLiMMA) graft copolymer is used as an interfacial layer in a Schottky diode for the first time. Au/poly (linoleic acid)-g-poly(methyl methacrylate) (PLiMMA)/n-Si diode was fabricated and main electrical characteristics of the diode were investigated using I–V measurements in dark and under illumination at room temperature. Ideality factor (n), barrier height (ΦB0) and serial resistance (Rs) values of the diode were found as 2.8, 0.87 eV and 8096 Ω for dark, and 6.3, 0.71 eV and 676 Ω for 100 mW/cm2 illumination intensity. Also, the reasons of deviation from ideal thermionic emission theory were investigated using Cheung&Cheung method and Card&Rhoderick's function which are used for calculating voltage dependence of barrier height (ΦB(V)), series resistance (Rs) and number of surface states (Nss) of the Au/PLiMMA/n-Si diode. 相似文献
996.
《Current Applied Physics》2015,15(6):703-705
Nanometer sized Ni-dot/Ag/Pt metal coating films with different Ni-dot sizes were incorporated in InGaN based blue light emitting diodes as p-type reflection metal to enhance the extraction efficiency of blue light. For the reflectivity change from 84% to 93.7%, the optical output power of blue light before phosphor coating and the luminous flux of white light after phosphor deposition have improved by 49.3% and 58.2% at 350 mA, respectively. For the presented white light devices, the blue and yellow luminescence respectively has been improved relatively up to 1.52 and 1.67 times. The improved extraction efficiency of yellow light from the phosphor integrated blue light emitting diode is thought to be attributed to the reduction of round trip loss of blue and yellow light inside the device due to the enhanced reflectivity of nanometer sized Ni/Ag/Pt p-type reflection metal. 相似文献
997.
A quartz-enhanced photoacoustic spectroscopy sensor for measurement of water vapor concentration in the air 下载免费PDF全文
Gong Ping Xie Liang Qi Xiao-Qiong Wang Rui Wang Hui Chang Ming-Chao Yang Hui-Xia Sun Fei Li Guan-Peng 《中国物理 B》2015,24(1):14206-014206
A compact and highly linear quartz-enhanced photoacoustic spectroscopy(QEPAS)sensor for the measurement of water vapor concentration in the air is demonstrated.A cost-effective quartz tuning fork(QTF)is used as the sharp transducer to convert light energy into an electrical signal based on the piezoelectric effect,thereby removing the need for a photodetector.The short optical path featured by the proposed sensing system leads to a decreased size.Furthermore,a pair of microresonators is applied in the absorbance detection module(ADM)for QTF signal enhancement.Compared with the system without microresonators,the detected QTF signal is increased to approximately 7-fold.Using this optimized QEPAS sensor with the proper modulation frequency and depth,we measure the water vapor concentration in the air at atmospheric pressure and room temperature.The experimental result shows that the sensor has a high sensitivity of 1.058parts-per-million. 相似文献
998.
Novel fluorene–isoindole-containing light-emitting mono- and oligomers were prepared. The synthesis of the monomers N-(4-bromo-phenyl)-2-(7-bromo-9,9-diethylfluoren-2-yl)-isoindole-1-carboxamide, N-(7-bromo-9,9-dibutylfluoren-2-yl)-2-(7-bromo-9,9-dibutylfluoren-2-yl)-isoindole-1-carboxamide, and N-[7-bromo-9,9-bis(2-ethylhexyl)-fluoren-2-yl]-2-[7-bromo-9,9-bis(2-ethylhexyl)-fluoren-2-yl]-isoindole -1-carboxamide was carried out by a three-component reaction of ortho-phthalaldehyde with the corresponding amine and isocyanide partners. The Ni(0) mediated polymerization reactions of the obtained monomers gave the corresponding mixture of oligomers from two up to twelve repeat units. The optical properties were also studied and it was found that the phenylene-containing oligomer emitted green light in dichloromethane solution, while both difluorene-containing oligomers, under the same conditions, proved to be blue light-emitters with good quantum efficiency. 相似文献
999.
Coumarin-cored carbazole dendrimers as solution-processed non-doped green emitters for electroluminescent devices 总被引:1,自引:0,他引:1
Narid Prachumrak Sirintra Potjanasopa Rattanawalee Rattanawan Supawadee Namuangruk Siriporn Jungsuttiwong Tinnagon Keawin Taweesak Sudyoadsuk Vinich Promarak 《Tetrahedron》2014
A series of green-emitting thiophenyl coumarin-cored carbazole dendrimers containing carbazole dendrons up to the third generation as substituent were synthesized and characterization. Their optical, thermal, electrochemical, and electroluminescent properties as non-doped solution-processed light-emitters for OLEDs were investigated. By incorporating carbazole dendrons in the molecule, we are able to reduce the crystallization and retain the high emissive ability of a planar thiophenyl coumarin fluorescent core in the solid state as well as improve the thermal stability of the material. These dendrimers showed a bright-green fluorescence and can form morphologically stable amorphous thin films with glass-transition temperatures as high as 285 °C. Simple structured solution-processed OLEDs using these materials as hole-transporting non-doped emitters and BCP as a buffer layer emit a stable green electroluminescence (λEL=502–526 nm) with high luminance efficiencies (up to 7.92 cd/A at 7.39 mA/cm2) and high green color purity (CIE=0.26, 0.62, which are close to the pure green color). 相似文献
1000.
以9,9'-(1,3-苯基)二-9H-咔唑(m CP)和1,4-二(三苯甲硅烷基)苯(UGH2)为母体,将常用的蓝光染料二(3,5-二氟-2-(2-吡啶)苯基-(2-吡啶甲酸根))合铱(Ⅲ)(FIrpic)掺入这两种母体材料中,制得具有双发光层结构的蓝色磷光有机电致发光器件,并对整个物理机制进行了阐述。该器件较基于m CP或UGH2为母体的单发光层器件有着更高的器件效率。器件的最大电流效率、功率效率、外量子效率分别为21.13 cd/A、14.97 lm/W、10.56%。器件亮度从100 cd/m2到3 000 cd/m2时,效率滚降为34.2%。 相似文献