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31.
新型高效太阳能电池研究进展 总被引:1,自引:0,他引:1
第三代太阳能电池以超高效率、薄膜化、低成本为主要目标,目前发展起来的有多结叠层太阳能电池、中间带太阳能电池、多激子产生太阳能电池、热载流子太阳能电池和热光伏太阳能电池等.文章简要介绍了以上几种新型太阳能电池的工作原理和最新进展,并对其发展前景作了分析和预测. 相似文献
32.
A silicon wafer implanted with a single low energy (42 keV) silicon ion beam results in strong luminescence at room temperature. The implantation results in the formation of various luminescent defect centers within the crystalline and polymorphous regions of the wafer. The resulting luminescence centers (LC) are mapped using fluorescence lifetime imaging microscopy (FLIM). The emission from the ion-implanted wafer shows multiple PL peaks ranging from the UV to the visible; these emissions originate from bound excitonic states in crystal defects and interfacial states between crystalline/amorphous silicon and impurities within the wafer. The LCs are created from defects and impurities within the wafer and not from nanoparticles. 相似文献
33.
34.
GaN激子跃迁的时间分辨光谱学研究 总被引:1,自引:1,他引:0
用时间分辨光谱学方法研究低压有机金属化学汽相沉积生长的GaN中自由,束缚激子(BX)的跃迁,讨论了这些跃迁的光致发光谱,复合寿命及其与温度的关系,给出了中性施主束缚激子和自由激子(FX)的辐射复合寿命分别为0.12ns和0.4ns。 相似文献
35.
A temperature-dependent integrated kinetics for the overall process of photosynthesis in green plants is discussed. The C4 plants are chosen and in these plants, the rate of photosynthesis does not depend on the partial pressure of O2. Using some basic concepts like chemical equilibrium or steady state approximation, a simplified scheme is developed for
both light and dark reactions. The light reaction rate per reaction center (R′
1) in thylakoid membrane is related to the rate of exciton transfer between chlorophyll neighbours and an expression is formulated
for the light reaction rate R′
1. A relation between R′
1 and the NADPH formation rate is established. The relation takes care of the survival probability of the membrane. The CO2 saturation probability in bundle sheath is also taken into consideration. The photochemical efficiency (ϕ) is expressed in terms of these probabilities. The rate of glucose production is given by R
glucose = (8/3)(R′
1
v
L
)ϕ(T)
g
(T) ([G3P]/[P
i]2
leaf)SS
Q
G3P→glucose where g is the activity quotient of the involved enzymes, and G3P represent glycealdehyde-3-phosphate in steady state. A Gaussian
distribution for temperature-dependence and a sigmoid function for de-activation are incorporated through the quotient g. In general, the probabilities are given by sigmoid curves. The corresponding parameters can be easily determined. The theoretically
determined temperature-dependence of photochemical efficiency and glucose production rate agree well with the experimental
ones, thereby validating the formalism. 相似文献
36.
用时间分辨光谱研究了很大的Te组分范围内的ZnS1-xTex(x=00 05—085)合金的发光动力学特性,结果表明:不同形态的Te等电子中心具有不同的辐射复 合寿命,从几个ns到几十个ns的范围内变化,当x=015左右时,寿命达到最大值(约 40ns).其物理机理源于不同的Te等电子中心具有不同的局域化特性.当Te组分较小时,等 电子中心从Te1逐渐演变到Te2,Te3或Te4 时,相应发光寿命增加,表现出不断增强 的激子发光局域化特性;而当Te组分较大时,Te原子团变得较大,其局域势与基体原子势的 相互作用增强,等电子中心的局域化特性减弱,而基体价带扩展态特征变得明显起来,相应 发光寿命逐渐减小.还研究了激子束缚能随Te组分的变化以及发光强度随温度的变化关系, 所得结果进一步支持了时间分辨光谱研究所得到的结论.
关键词:
ZnS
等电子中心
时间分辨光谱
局域态 相似文献
37.
JIANG Yong-Jin TAO Rui-Bao 《理论物理通讯》2001,(11)
A pair of up-down operators are constructed explicitly for S.C.Zhang‘s SO(5) theory of high Tc superconductivity.From them two good quantum numbers are derived.The up-down operators are related to the spin-independent excitons which are not considered before.`` 相似文献
38.
A. V. Mudryi A. V. Ivanyukovich M. V. Yakushev R. Martin A. Saad 《Journal of Applied Spectroscopy》2007,74(3):415-420
The effect of a strong magnetic field (induction up to 10 T) on free and bound excitons in CuInS2 single crystals is studied. A diamagnetic shift to higher energies is observed in the luminescence and reflectance spectra
for free-exciton lines ALPB ≈ 1.5348 eV, AUPB ≈ 1.5361 eV, and BC ≈ 1.557 eV. The diamagnetic shifts of free-exciton lines ALPB, AUPB, and BC provide a basis for estimating the exciton reduced masses
= 0.131m0,
= 0.13 4m0, and μBC = 0.111m0, respectively. Bound-exciton lines in luminescence spectra are split under the influence of the magnetic field. The magnitude
of the Zeeman effect (g-factor of the magnetic splitting) is estimated.
__________
Translated from Zhurnal Prikladnoi Spektroskopii Vol. 74, No. 3, pp. 373–377, May–June, 2007. 相似文献
39.
Prof. Dr. Suning Wang Deng‐Tao Yang Jiasheng Lu Hiroyuki Shimogawa Prof. Dr. Shaolong Gong Xiang Wang Soren K. Mellerup Prof. Dr. Atsushi Wakamiya Dr. Yi‐Lu Chang Prof. Dr. Chuluo Yang Prof. Dr. Zheng‐Hong Lu 《Angewandte Chemie (International ed. in English)》2015,54(50):15074-15078
New BN‐heterocyclic compounds have been found to undergo double arene photoelimination, forming rare yellow fluorescent BN‐pyrenes that contain two B? N units. Most significant is the discovery that the double arene elimination can also be driven by excitons generated electrically within electroluminescent (EL) devices, enabling the in situ solid‐state conversion of BN‐heterocycles to BN‐pyrenes and the use of BN‐pyrenes as emitters for EL devices. The in situ exciton‐driven elimination (EDE) phenomenon has also been observed for other BN‐heterocycles. 相似文献
40.
Efficiency Improvement in Polymer Light‐Emitting Diodes by “Far‐Field” Effect of Gold Nanoparticles 下载免费PDF全文
Xiaoyan Wu Linlin Liu Zhicong Deng Li Nian Wenzhuo Zhang Dehua Hu Zengqi Xie Yueqi Mo Yuguang Ma 《Particle & Particle Systems Characterization》2015,32(6):686-692
The “far‐field” effect of metal nanoparticles (NPs), when chromophores localized nearby metal NPs (typically the distance >λ/10), is an important optical effect to enhance emission in photoluminescence. The far‐field effect originates mainly from the interaction between origin emission and mirror‐reflected emission, resulting in the increased irradiative rate of chromophores on the mirror‐type substrate. Here, the far‐field effect is used to improve emission efficiency of polymer light‐emitting diodes (PLEDs). A universal performance improvement is achieved for the full visible light (red, green, blue) PLEDs, utilizing gold (Au) NPs to modify the indium tin oxide (ITO) substrates; this is shown by experimental and theoretical simulation to mainly come from the far‐field effect. The optimized distance, between the NPs and chromophores with visible light emission ranging from 400 to 700 nm, is 80–120 nm. Thus the scope of the far‐field may overlap the light‐emitting profile very well to enhance the efficiency of optoelectronic devices. The 30–40% enhancement is obtained for different color‐emitting materials through distance optimization. The far‐field effect is demonstrated to enhance device performance for materials in the full‐visible spectral range, which extends the optoelectric applications of Au NPs. 相似文献