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71.
J. H. Wu S. C. Hao Z. Lan J. M. Lin M. L. Huang Y. F. Huang L. Q. Fang S. Yin T. Sato 《Advanced functional materials》2007,17(15):2645-2652
Dye‐sensitized solar cells (DSSCs) are receiving considerable attention as low‐cost alternatives to conventional solar cells. In DSSCs based on liquid electrolytes, a photoelectric efficiency of 11 % has been achieved, but potential problems in sealing the cells and the low long‐term stability of these systems have impeded their practical use. Here, we present a thermoplastic gel electrolyte (TPGE) as an alternative to the liquid electrolytes used in DSSCs. The TPGE exhibits a thermoplastic character, high conductivity, long‐term stability, and can be prepared by a simple and convenient protocol. The viscosity, conductivity, and phase state of the TPGE can be controlled by tuning the composition. Using 40 wt % poly(ethylene glycol) (PEG) as the polymeric host, 60 wt % propylene carbonate (PC) as the solvent, and 0.65 M KI and 0.065 M I2 as the ionic conductors, a TPGE with a conductivity of 2.61 mS cm–2 is prepared. Based on this TPGE, a DSSC is fabricated with an overall light‐to‐electrical‐energy conversion efficiency of 7.22 % under 100 mW cm–2 irradiation. The present findings should accelerate the widespread use of DSSCs. 相似文献
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73.
高稳定高能量被动调Q激光 总被引:1,自引:1,他引:1
在普通被动调Q激光器中引入抗共振环(ARR)结构。以Cr^4 :YAG晶体、BDN染料片和LiF:F2^-色心晶体作为可饱和吸收体,采用平面-ARR介稳腔和凸-ARR非稳腔,得到了输出能量大于80mJ、超伏小于1.5%的高稳定大能量调Q单脉冲输出。利用ARR的光栅效应和饱和吸收的机理很好地解释了实验结果。 相似文献
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76.
同时测量氢和氧CARS谱的新方法 总被引:1,自引:0,他引:1
提出一种仅需一台染料激光器即可同时测量火焰中氢和氧的CARS谱的新方法.取带宽为120cm~(-1).中心波长位于580.4nm的Stokes光束与532nm的泵浦光束相配合.同时测量氢扩散火焰中的氢和氧的CARS谱.用氢的S(6)和S(5)的积分强度比确定火焰中的温度并与氮的Q支CARS谱测量的温度和经过热损耗修正的热电偶测得的温度取得了相当好的一致结果.一次测出氢和氧的CARS谱.避免多次测量中参数的难以重复性.提高了以温度为参数来确定浓度的准确性. 相似文献
77.
Environment friendly and efficient strategy for the preparation of titanium dioxide (TiO2)–graphene (GR) based hybrid nanocomposite has been demonstrated by simple chemical approach for the photodegradation of Acid Orange 7 (AO7) dye under solar irradiation. The resultant nanocomposite structure and composition has been characterized by Ultraviolet Diffusive Reflectance Spectroscopy (UV-DRS), Fourier Transform Infrared Spectroscopy (FTIR), Thermogravimetric Analysis (TGA), Raman spectroscopy and X-ray diffraction (XRD) studies. The incorporation of TiO2 nanoparticles on the surface of GR was confirmed by High Resolution Transmission Electron Microscopy (HRTEM) and Field Emission Scanning Electron Microscopy (FESEM) studies. Electrochemical Impedance spectroscopy (EIS) and Cyclicvoltammetry (CV) studies revealed that the incorporation of GR with TiO2 nanoparticles significantly enhanced the redox property and electrical conductivity. During photocatalysis, the TiO2–GR nanocomposites have high photocatalytic activity compared with that of TiO2 towards AO7 dye degradation under solar light irradiation. The enhanced photocatalytic activity might be attributed to the role GR played as an electron acceptor and transporter in the composite film, which effectively suppressed the charge recombination and promoted the charge transfer within the composite. 相似文献
78.
Chung‐Wei Kung Hsin‐Wei Chen Chia‐Yu Lin Yi‐Hsuan Lai R. Vittal Kuo‐Chuan Ho 《Progress in Photovoltaics: Research and Applications》2014,22(4):440-451
A double‐layer film, consisting of an upper layer of ZnO nanosheets and a lower layer of ZnO nanoparticles (designated as ZnONS/NP), was synthesized for the photoanode of a dye‐sensitized solar cell (DSSC) by a one‐step potentiostatic electrodeposition on a conducting fluorine‐doped tin oxide substrate at 70 °C in a solution containing zinc nitrate and sodium acetate, followed by the pyrolysis of the film at 300 °C. The growth mechanism of the double‐layer nanostructure was studied by monitoring the morphological changes at various periods of electrodeposition. The effects of the concentration of acetate anion on the morphology of the double‐layer structure were also studied. The double‐layer film of ZnONS/NP showed a better self‐established light scattering property, compared with that of a thin film of ZnO nanoparticles, prepared without acetate anion. The concentration of an acetate anion in the electrolyte for the electrodeposition of the double‐layer film, the electrodeposition period, and the period for dye adsorption were optimized for obtaining the best performance for a DSSC with a photoanode consisting of the double layer. A metal‐free dye, coded as D149, was used in this research. A conversion efficiency of 4.65% was achieved for a DSSC (0.2376 cm2) with the photoanode, consisting of the double‐layer film, under 100 mW/cm2 illumination in the wavelength range of 400–800 nm. X‐ray diffraction patterns, thermo gravimetric curves, elemental analysis, scanning electron microscopic images, transmission electron microscopic image, transmission spectra, and electrochemical impedance spectra were used to explain observations. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
79.
本文对染料激光用调谐器进行了理论分析,提出了同时兼顾调谐灵敏度,输出光强度及输出激光线宽等因素的综合设计方案。 相似文献
80.
Ligand‐Free Synthesis of Aluminum‐Doped Zinc Oxide Nanocrystals and their Use as Optical Spacers in Color‐Tuned Highly Efficient Organic Solar Cells 下载免费PDF全文
Meriem Gaceur Sadok Ben Dkhil David Duché Fatima Bencheikh Jean‐Jacques Simon Ludovic Escoubas Mahdi Mansour Antonio Guerrero Germà Garcia‐Belmonte Xianjie Liu Mats Fahlman Walid Dachraoui Abdou Karim Diallo Christine Videlot‐Ackermann Olivier Margeat Jörg Ackermann 《Advanced functional materials》2016,26(2):243-253
The color of polymer solar cells using an opaque electrode is given by the reflected light, which depends on the composition and thickness of each layer of the device. Metal‐oxide‐based optical spacers are intensively studied in polymer solar cells aiming to optimize the light absorption. However, the low conductivity of materials such as ZnO and TiO2 limits the thickness of such optical spacers to tenths of nanometers. A novel synthesis route of cluster‐free Al‐doped ZnO (AZO) nanocrystals (NCs) is presented for solution processing of highly conductive layers without the need of temperature annealing, including thick optical spacers on top of polymer blends. The processing of 80 nm thick optical spacers based on AZO nanocrystal solutions on top of 200 nm thick polymer blend layer is demonstrated leading to improved photocurrent density of 17% compared to solar cells using standard active layers of 90 nm in combination with thin ZnO‐based optical spacers. These AZO NCs also open new opportunities for the processing of high‐efficiency color tuned solar cells. For the first time, it is shown that applying solution‐processed thick optical spacer with polymer blends of different thicknesses can process solar cells of similar efficiency over 7% but of different colors. 相似文献