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The preparation and characteristics of a transparent conducting indium zinc tin oxide ͑IZTO͒ anode for highly efficient phosphorescent organic light emitting diodes ͑OLEDs͒ is described. The resistivity and transmittance of the IZTO anode are comparable to reference In 2 O 3 ͑ITO͒ anode films even though it was prepared at room temperature. In addition, the work function of the ozone-treated amorphous IZTO anode ͑5.12 ± 0.02 eV͒ is much higher than that of ozone-treated reference ITO anodes ͑4.94 ± 0.02 eV͒. The current-voltage-luminance characteristics and efficiencies of OLEDs prepared on the IZTO anode are critically dependent on the sheet resistance of the IZTO anode. Furthermore, both the quantum efficiency and power efficiency of the OLED fabricated on the amorphous IZTO anode are much higher than those of an OLED with the reference ITO anode due to the higher work function of the IZTO anode than those of conventional ITO anode. This indicates that IZTO is an alternative material for conventional ITO anodes used in OLEDs and flexible displays.Organic light emitting diodes ͑OLEDs͒ are of considerable importance for their potential as a new generation of flat panel displays and flexible displays due to their high peak brightness, high dark room contrast, low power consumption, low-cost, super viewing ability, and fast response time. 1,2 In order to obtain highperformance OLEDs and flexible OLEDs, it is very important to develop a high-quality anode layer with low resistance, high transparency, chemical stability, and a high work function. 1,2 Although Sn-doped In 2 O 3 ͑ITO͒ has been commonly used in OLEDs and flexible OLEDs as an anode material due to high conductivity and transmittance in visible range, the conventional ITO anode has several problems, such as an imperfect work function alignment, chemical instability, high process temperature, and easy deterioration of the ITO target. 3,4 Recently, both ternary oxide and multicomponent oxides, such as Al-Zn-O ͑AZO͒, Ga-Zn-O ͑GZO͒, Zr-Zn-O ͑ZZO͒, In-Ga-O ͑IGO͒, In-Zn-O ͑IZO͒, In-Ga-Sn-O ͑IGTO͒, and Zn-In-Sn-O ͑IZTO͒ have gained much attention as promising anode materials for OLED and flexible OLEDs. 3,5-7Among the various multicomponent-TCO materials, IZTO films have recently been recognized as attractive anode materials in OLEDs and flexible OLEDs due to their high work function, good conductivity, high-transparency, and low-deposition temperature. 3 Phillips et al. reported that Zn x In 2−y SnyO 3+x−␦ film grown by pulsed laser deposition and sputtering has high conductivity and transmittance within ranges typically reported for ITO films. 8 In addition, Ambrosini et al., investigating zinc doping in cosubstituted In 2−2x Sn x Zn x O 3−␦ bulk pellet, found that the solubility of ZnO and SnO 2 in In 2 O 3 can be greatly increased up to x = 0.4 by codoping with equal amounts of Zn and Sn in the In 2 O 3 . 9 Mark et al., in an investigation of the high work function transparent conducting oxide as an anode for an OLED, reported that an IZTO film has a higher ...

The preparation of Fe doped TiO 2 is demonstrated as well as application for gas sensing and photocatalytic degradation. Fe doped TiO 2 nanopowder was prepared by the mechanochemical ball milling method. The results show the uniform doping of Fe in TiO 2 powder. The average size of the particle is observed to be ∼28 nm. The H 2 gas sensor was fabricated using the Fe doped TiO 2 nanopowder and the effect of Fe doping on the sensing properties is investigated with various temperature ranges. The prepared Fe doped TiO 2 nanoparticles are also used to explore degradation properties of Rhodamine B dye under LED light.

ZnO nanorods and thin films were synthesized on Si(100) substrates at a low temperature by controlling the ZnO seed formation in an aqueous solution process. Vertically well-aligned ZnO nanorods with a single-crystalline hexagonal structure and c-axis growth orientation were obtained despite having a different crystal structure than a large lattice mismatch with the Si(100) substrate. In addition, the authors suggest that the lateral growth of ZnO nanorods causes them to merge together into ZnO thin films during growth into the aqueous solution. It is also suggested that the significant blueshift of the main emission band in the photoluminescence spectrum obtained from the nanorod sample at 10 K can be mainly attributed to Burstein-Moss effects in the ZnO nanorods.

We made the ZnO nanorods using wet chemical method. it is so simple, economic and suitable for large-scale production, the quality of the arrayed ZnO nanorods fabricated using these methods are not as good as that of nanorods prepared via VLD, CVDand ED method. We demonstrate that the concentration of precursors have influence on the morphology and optical properties, growth density and its distribution of the arrayed ZnO nanorods can be effectively controlled by using suitable conditions. We tried to study suitable ZnO nanorods growth condition to apply to a organic-inorganic hybrid solar cell, and we made the solar cell and investigated the energy conversion efficiency etc.

The behavior of water and gas distribution in the gas diffusion layers (GDLs) of proton exchange membrane fuel cells (PEMFCs) were investigated analytically. In order to prevent the flooding phenomenon of the electrodes by the product water, gas diffusion layer is usually hydrophobed. Formerly, gas diffusion layer was partially coated with PTFE (polytetrafluroethylene) suspension but flakingoff of PTFE particles were observed. In this study, gas diffusion layer is coated with HTTS ((hepradecafluoro-1,1,2,2-tetrahydrodecyl)triethoxysilane)-derived layers having hydrophobic functional group. The influence of the HTTS coating on gas permeability and hydrophobicity of gas diffusion layer are analyzed and discussed.

The characteristics of a SiN x passivation layer grown by a specially designed catalyzer-enhanced chemical vapor deposition ͑CECVD͒ system for top-emitting organic light-emitting diodes ͑TOLEDs͒ were investigated. Using a tungsten catalyzer connected in series, a high-density SiN x passivation layer with high transmittance was deposited on TOLEDs at a substrate temperature of 50°C. Even at low substrate temperature, 150 nm thick SiN x passivation layer prepared by CECVD exhibited a low water vapor transmission rate of 2-6 ϫ 10 −2 g/m 2 /day. In addition, it was found that the transmittance of SiN x film at 550 nm was significantly influenced by the hydrogen flow rate. Current density-voltage-luminescence results of TOLEDs passivated with a 150 nm thick SiN x film indicated that the electrical and optical properties of TOLEDs were not affected by the high temperature tungsten catalyzer during the SiN x deposition. The lifetime to half initial luminance of a TOLED passivated with a 150 nm thick SiN x layer was much longer than that of a nonpassivated reference sample. This shows that the CECVD is a promising plasma free thin-film passivation technique for high-performance TOLEDs and flexible displays.

We report the controlled synthesis of dumbbell shaped ZnO micro/nanostructures using anionic surfactant sodium dodecyl sulphate (SDS) by simple one-step hydrothermal method. The morphology changes of ZnO were characterized by using scanning electron microscopy, X-ray diffraction, and energy dispersive spectroscopy. It is found that the size of the dumbbell increased with increase in concentration of SDS. Systematic growth mechanism with increase of concentration of SDS polymer is studied. Our results will help in the growing face selective ZnO for many functional applications.