排序方式: 共有47条查询结果,搜索用时 15 毫秒
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Teen Hang Meen Jenn Kai Tsai Yu Shin Tu Tian Chiuan Wu Wen Dung Hsu Shoou-Jinn Chang 《Nanoscale research letters》2014,9(1):523
In this study, the P25 titanium dioxide (TiO2) nanoparticle (NP) thin film was coated on the fluorine-doped tin oxide (FTO) glass substrate by a doctor blade method. The film then compressed mechanically to be the photoanode of dye-sensitized solar cells (DSSCs). Various compression pressures on TiO2 NP film were tested to optimize the performance of DSSCs. The mechanical compression reduces TiO2 inter-particle distance improving the electron transport efficiency. The UV–vis spectrophotometer and electrochemical impedance spectroscopy (EIS) were employed to quantify the light-harvesting efficiency and the charge transport impedance at various interfaces in DSSC, respectively. The incident photon-to-current conversion efficiency was also monitored. The results show that when the DSSC fabricated by the TiO2 NP thin film compressed at pressure of 279 kg/cm2, the minimum resistance of 9.38 Ω at dye/TiO2 NP/electrolyte interfaces, the maximum short-circuit photocurrent density of 15.11 mA/cm2, and the photoelectric conversion efficiency of 5.94% were observed. Compared to the DSSC fabricated by the non-compression of TiO2 NP thin film, the overall conversion efficiency is improved over 19.5%. The study proves that under suitable compression pressure the performance of DSSC can be optimized. 相似文献
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Teen-Hang Meen Ying-Chung Chen Ken-Whie Liaw Hung-Duen Yang 《Journal of the American Ceramic Society》1993,76(8):1948-1952
X-ray diffraction patterns show that most samples of Y1-x Prx Ba2 Cu4 O8 examined in the present study contained a single YBa2 Cu4 O8 (1-2-4) superconductive phase for x<0.7.Lattice parameters a and b increased with Pr concentration, suggesting that most of the Pr is trivalent in Y1-x Prx- Ba2 Cu4 O8 . The zero-resistance temperature, T co , decreases monotonically from 80 K at x=0 to 12 K at x=0.65, and superconducting transition widths tend to broaden for x>0. The room-temperature resistivity changes linearly until x=0.7 and increases abruptly at x=-0.75. The critical concentration, xcr , thus was estimated to be 0.7. The effective magnetic moments of Pr in Y 1-x Prx Ba2 Cu4 O8 were 3.63., 3.35, and 3.23, μB for x=0.2, 0.4 and 0.6, respectively. In the R0.8 Pr0.2 Ba2 Cu4 O8 system, the depression of Tc weakly depends on the ionic radius of rare-earth elements. Similarities and differences between Y 1-x Prx Ba2 Cu4 O8 and Y1-x Prx- Ba2 Cu3 O7-y also were noted and are discussed in this paper. 相似文献
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Geoffrey Meen 《Journal of Housing and the Built Environment》2011,26(3):263-276
Unsurprisingly, a great deal of attention has been paid to the economic consequences of the credit crunch. However, this paper
shows that the credit crunch was preceded by a strong build-up of mortgage debt internationally, which, in the long run, could
turn out to be more significant than the credit crunch itself. Indeed, the debt build-up suggests that the credit crunch is
more likely to reoccur, because highly-indebted households have weaker buffers to withstand unexpected shocks to their incomes
or to interest rates. The paper presents a model that can explain the debt build-up and changes to the distribution of debt
between existing owners and first-time buyers, which hinders access to home-ownership for the latter, even amongst those households
who would be considered as credit-worthy. 相似文献
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Improved the efficiency of small molecule organic solar cell by double anode buffer layers 总被引:1,自引:0,他引:1
Chien-Jung Huang Jhong-Ciao KeWen-Ray Chen Teen-Hang MeenCheng-Fu Yang 《Solar Energy Materials & Solar Cells》2011,95(12):3460-3464
Small molecule organic solar cell with an optimized hybrid planar-mixed molecular heterojunction (PM-HJ) structure of indium tin oxide (ITO)/ poly(3,4-ethylenedioxythiophene): poly(styrenesulfonate) (PEDOT: PSS) doped with 4 wt% sorbitol/ pentacene (2 nm)/ copper phthalocyanine (CuPc) (10 nm)/ CuPc: C60 mixed (20 nm)/ fullerene (C60) (20 nm)/ bathocuproine (BCP) (10 nm)/Al was fabricated. PEDOT: PSS layer doped with 4 wt% sorbitol and pentacene layer were used as interlayers between the ITO anode and CuPc layer to help the hole transport. And then the short-circuit current (Jsc) of solar cell was enhanced by inserting both the PEDOT: PSS (4 wt% sorbitol) and the pentacene, resulting in a 400% enhancement in power conversion efficiency (PCE). The maximum PCE of 3.9% was obtained under 1sun standard AM1.5G solar illumination of 100 mW/cm2. 相似文献
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C. J. Huang T. H. Meen M. Y. Lai W. R. Chen 《Solar Energy Materials & Solar Cells》2004,82(4):553-565
This work reveals the formation of electrodeposition (ED) of CuInSe2 (CIS) film on flexible substrate. Ternary compounds were co-deposited on Au coated plastic substrate from an aqueous acidic solution containing 1 mM CuCl2, 5 mM InCl3 and 1 mM SeO2 adjusted to pH=1.65. It was found that the film stoichiometry improves when the growth solution consisted of 1 M triethanolamine (TEA) and 0.1 M Na-citrate. The optimal ED-CIS film was obtained after annealing at 150°C for 1 h in a nitrogen (N2) atmosphere. Optical absorption study showed that the energy gap of the annealed material is 1.18 eV. Good and reliable quality ED-CIS film was grown in this research with the potential use in fabricating flexible solar cells. This was supported by various analytical techniques, including energy dispersive spectroscopy (EDS), X-ray diffraction spectroscopy (XRD), scanning electron microscopy (SEM), ultraviolet/visible spectroscopy, Fourier transform infrared spectrometer (FTIR) and photoelectrochemical (PEC) characterization. 相似文献
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D.W. Chou C.J. Huang C.M. Su C.F. Yang W.R. Chen T.H. Meen 《Solid-state electronics》2011,61(1):76-80
The bottom contact pentacene-based thin-film transistor is fabricated, and it is treated by rapid thermal annealing (RTA) with the annealed temperature up to 240 °C for 2 min in the vacuum of 1.3 × 10−2 torr. The morphology and structure for the pentacene films of OTFTs were examined by scanning electron microscopy and X-ray diffraction technique. The thin-film phase and a very small fraction of single-crystal phase were found in the as-deposited pentacene films. While the annealing temperature increases to 60 °C, the pentacene molecular ordering was significantly improved though the grain size only slightly increased. The device annealed at temperature of 120 °C has optimal electrical properties, being consistent with the experimental results of XRD. The post-annealing treatment results in the enhancement of field-effect mobility in pentacene-based thin-film transistors. The field-effect mobility increases from 0.243 cm2/V s to 0.62 cm2/V s. Besides, the threshold voltage of device shifts from −7 V to −3.88 V and the on/off current ratio increases from 4.0 × 103 to 8.7 × 103. 相似文献
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Teen-Hang Meen Jenn-Kai Tsai Shi-Mian Chao Yu-Chien Lin Tien-Chuan Wu Tang-Yun Chang Liang-Wen Ji Walter Water Wen-Ray Chen I-Tseng Tang Chien-Jung Huang 《Nanoscale research letters》2013,8(1):450
In this study, we prepared different shapes of gold nanoparticles by seed-mediated growth method and applied them on the photoelectrodes of dye-sensitized solar cells (DSSCs) to study the surface plasma resonant (SPR) effect of gold nanoparticles on the photoelectrodes of dye-sensitized solar cells. The analyses of field emission scanning electron microscopy show that the average diameter of the spherical gold nanoparticles is 45 nm, the average length and width of the short gold nanorods were 55 and 22 nm, respectively, and the average length and width of the long gold nanorods were 55 and 14 nm, respectively. The aspect ratio of the short and long gold nanorods was about 2.5 and 4, respectively. The results of ultraviolet–visible absorption spectra show that the absorption wavelength is about 540 nm for spherical gold nanoparticles, and the absorption of the gold nanorods reveals two peaks. One is about 510 to 520 nm, and the other is about 670 and 710 nm for the short and long gold nanorods, respectively. The best conversion efficiency of the dye-sensitized solar cells with spherical gold nanoparticles and short and long gold nanorods added in is 6.77%, 7.08%, and 7.29%, respectively, and is higher than that of the cells without gold nanoparticles, which is 6.21%. This result indicates that the effect of gold nanoparticles on the photoelectrodes can increase the conductivity and reduce the recombination of charges in the photoelectrodes, resulting in the increase of conversion efficiency for DSSCs. In addition, the long gold nanorods have stronger SPR effect than the spherical gold nanoparticles and short gold nanorods at long wavelength. This may be the reason for the higher conversion efficiency of DSSCs with long gold nanorods than those of the cells with spherical gold nanoparticles and short gold nanorods. 相似文献
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Microsystem Technologies - 相似文献
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This work demonstrates the improvement of the color purity and electrical characteristics for flexible red-light organic light emitting devices (FROLEDs). The devices were prepared by vacuum deposition on ITO-plastic substrates. These guest materials of DCJTB and Rubrene were doped into the host material of Alq3, resulting in an emitting layer. Experimental results reveal that the properties in the above case are better than those of the emitting layer with a single DCJTB guest material, reaching the commercial red-light wavelength requirement of 620 nm. Furthermore, the brightness of FROLED at the concentration ratio [3.0:7] may be two times higher because the presence of Rubrene enhances the effective transmission of energy from Alq3 to DCJTB. 相似文献