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151.
Pumping dye-doped organic polymer by interference pattern of a frequency-doubled Nd:YAG 532 nm laser to induce a periodic gain-structure and confining it within a stable optical resonator, the oscillation output can be effectively enhanced in comparison with either that of uniform irradiation, i.e., pumping, or of distributed feedback (DFB) operation, and the oscillation wavelength becomes tunable by adjusting the period of the interference pattern. Using Rhodamine-B as a dopant over the range from 200 to 1000 ppm, the oscillation output was enhanced by - 10 dB, which was larger than the output of the uniform irradiation and was - 30% greater than the DFB scheme. Moreover, changing the period of the interference pattern by adjusting the setting angle of the Koster prism enables us to vary the oscillation wavelength around 600 nm. 相似文献
152.
Jian‐Ging Chen Ken‐Yen Liu Chia‐Yuan Chen Chia‐Yu Lin Kuan‐Chieh Huang Yi‐Hsuan Lai Chun‐Guey Wu King‐Fu Lin Kuo‐Chuan Ho 《Journal of polymer science. Part A, Polymer chemistry》2010,48(22):4950-4957
This study reports the characteristics of gel‐type dye‐sensitized solar cells (DSSCs), fabricated with gel‐type electrolyte containing poly‐1,1′‐(methylenedi‐4,1‐phenylene)bismaleimide (PBMI), or poly‐1,1′‐(3,3′‐dimethyl‐1,1′‐biphenyl‐4,4′‐diyl)bismaleimide (PDBBMI), or poly‐N,N′‐(4‐methyl‐1,3‐phenylene)bismaleimide (PMPBMI), prepared by in situ polymerization of the corresponding monomer without an initiator at 30 °C. Incorporating 0.3 wt % content of exfoliated alkyl‐modified nanomica (EAMNM) into PBMI‐gelled electrolyte leads to higher short‐circuit current density (Jsc = 17.14 mA cm?2) and efficiency (η = 7.02%) than that of neat PBMI‐gel electrolyte (Jsc = 15.32 mA cm?2, η = 6.41%). Incorporating 0.3 wt % EAMNM into PBMI‐gelled electrolyte results in remarkably stable device performance under continuous light soaking under one sun (100 mW cm?2) at 55 °C. The efficiency of DSSCs based on PBMI/0.3 wt % EAMNM‐gelled electrolyte drops by only 1.7% (η = 6.93%) after 500 h of continuous light soaking. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2010 相似文献
153.
YAN Yue ZHAO SuLing XU Zheng WEI Gong & WANG LiHui Institute of Optoelectronic Technology Beijing Jiaotong University Beijing China Key Laboratory of Luminescence Optical Information Ministry of Education Department of Physics Chinese People’s Public Security University Beijing 《中国科学:物理学 力学 天文学(英文版)》2011,(3)
We fabricate inverted organic/inorganic hybrid solar cells based on vertically oriented ZnO nanorods and polymer MEH-PPV. The morphology of ZnO nanorods and ZnO nanorods/MEH-PPV hybrid structure is depicted by using scanning electron microscopy (SEM), X-ray diffraction (XRD), and atomic force microscope (AFM), respectively. It is observed that ZnO nanorods array grows primarily aligned along the perpendicular direction of the ITO substrate. The MEH-PPV molecule does not enter the interspace between ZnO nano... 相似文献
154.
155.
156.
Yamin Feng Jinghua Chen Xintang Huang Weifeng Liu Yu Zhu Wei Qin Xiaoyuan Mo 《Crystal Research and Technology》2016,51(10):548-553
A dye‐sensitized solar cell (DSSC) based on ZnO/TiO2 composite nanorods (NRs) photoanode is fabricated. The power conversion efficiency (PCE) of the ZnO/TiO2 composite NRs film DSSC is 4.36%, which is obviously higher than that of DSSCs based on pure TiO2 NRs (0.6%) and ZnO NRs (3.10%). The enhanced performance of ZnO/TiO2 composite NRs film DSSC can be attributed to the combined effects of ZnO and TiO2 NRs. In this architecture, the thick ZnO NRs overlayer offers a large surface area for enough dye absorption, while the thin TiO2 NRs underlayer not only offers a direct and quick pathway for photoinjected electron transfer along the photoanode but also acts as a blocking layer, which effectively hinders the direct contact between the substrate and the electrolyte resulting in lower carrier recombination. 相似文献
157.
Computational studies on optoelectronic and charge transfer properties of some perylene‐based donor‐π‐acceptor systems for dye sensitized solar cell applications
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Taniya Manzoor Summera Asmi Saba Niaz Altaf Hussain Pandith 《International journal of quantum chemistry》2017,117(5)
We report DFT studies on some perylene‐based dyes for their electron transfer properties in solar cell applications. The study involves modeling of different donor‐π‐acceptor type sensitizers, with perylene as the donor, furan/pyrrole/thiophene as the π‐bridge and cyanoacrylic group as the acceptor. The effect of different π‐bridges and various substituents on the perylene donor was evaluated in terms of opto‐electronic and photovoltaic parameters such as HOMO‐LUMO energy gap, λmax, light harvesting efficiency(LHE), electron injection efficiency (Øinject), excited state dye potential (Edye*), reorganization energy(λ), and free energy of dye regeneration (). The effect of various substituents on the dye–I2 interaction and hence recombination process was also evaluated. We found that the furan‐based dimethylamine derivative exhibits a better balance of the various optical and photovoltaic properties. Finally, we evaluated the overall opto‐electronic and transport parameters of the TiO2‐dye assembly after anchoring the dyes on the model TiO2 cluster assembly. 相似文献
158.
In order to study the droplet pattern and electro-optic (EO) behaviour of polymer dispersed liquid crystal (PDLC) with the addition of dye, dichroic polymer dispersed liquid crystal (DPDLC) films were prepared using a nematic liquid crystal (NLC), photo-curable polymer (NOA 65) and anthraquinone blue dichroic dye (B2), in equal ratio (1:1) of polymer and liquid crystal (LC) by polymerisation induced phase separation (PIPS) technique. Dichroic dye was taken in different concentration (wt./wt. ratio) as 0.0625%, 0.125%, 0.25%, 0.5% and 1% of the LC mixture in DPDLC films. Initially, in an open circuit when there is no proviso for external electric field (0 V), LC droplets in polymer matrix exhibited bipolar pattern, though on closing the circuit with the increase of electric field pattern of droplets starts changing, LC molecules align along the direction of applied electric field and aligned completely relatively at higher field (30 V), which illustrate vertical radial pattern. Further, results show that the DPDLC film containing 0.0625% dye concentration with consistent average droplet size ~4.30 μm, exhibits the best transmission at lower operating voltage. 相似文献
159.
In this paper, we described the synthesis and characterization of new diphenylethylene bearing imino group. We concentrated particularly on the investigation of the possibility of the excited state intramolecular charge transfer (ESIPT) of the new dyes experimentally and theoretically. The absorption and fluorescence spectroscopy of the dyes were determined in various solvents. The results showed that the maximal absorption wavelength of 2‐[(4′‐N,N‐dimethylamino‐diphenylethylene‐4‐ylimino)methyl]phenol ( C1 ) and 4‐[(4′‐N,N‐dimethylamino‐diphenylethylene‐4‐ylimino)methyl]phenol ( C2 ) exhibited almost independence on the solvent polarity. While as contrast, the maximal fluorescence wavelength of the dyes showed somewhat dependence on the solvent polarity. In particular, C1 displayed well‐separated dual fluorescence spectroscopy. The second fluorescence peak was characterized with an "abnormal" fluorescence emission wavelength in aprotic solvents with large Stokes shift (ca. 140 nm in THF), which was much more than normal Stokes shift (ca. 30 nm in THF). This emission spectroscopy could be assigned to ESIPT emission. On the other hand, the ESIPT fluorescence of C1 was much reduced or lost in the protic solvents. While, only normal fluorescence emission was detected in various solvents. Although the absorption maxima of C1 exhibited about 10 nm red‐shift with respect to those of C2 , the normal fluorescence maxima of C1 and C2 were almost identical in various solvents. These results suggested that C1 could undergo ESIPT, but C2 was not able to proceed ESIPT. The molecular geometry optimization of phototautomers in the ground electronic state (S0) was carried out with HF method (Hartree‐Fock) and at DFT level (Density Functional Theory) using B3LYP both, while the CIS was employed to optimize the geometries of the first singlet excited state (S1) of the phototautomers of C1 and C2 respectively. The properties of the ground state and the excited state of the phototautomers of C1 and C2 , including the geometrical parameter, the energy, the frontier orbits, the Mulliken charge and the dipole moment change were performed and compared completely. The data were analyzed further based on our experimental results. Furthermore, the absorption and fluorescence spectra were calculated in theory and compared with the measured ones. The rate constant of internal proton transfer (9.831×1011 s?1) of C1 was much lower than that of salicylidene methylamine ( C3 , 2.045×1015 s?1), which was a typical Schiff base compound and was well demonstrated to undergo ESIPT easily under photoexcitation. 相似文献
160.
建立了微波消解-石墨炉原子吸收光谱法测定植物染发剂中重金属铅、镉和铜的方法.采用L9(34)正交设计讨论了固液比、消解剂体积比、消解时间和消解压力对样品消解效果的影响,最佳的消解条件:固液比(g/mL)为1∶12,HNO3/H2O2(V/V)为4∶1,消解时间为5min,消解压力1.5MPa.在最佳微波消解条件下,进行了精密度实验、回收率实验,相对标准偏差为1.05%~3.35%,回收率为96.67%~105.43%.微波消解法处理植物染发剂样品,试剂用量少、消解完全、快速、简便,而且测定结果的精密度、准确度较好. 相似文献