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1.
王婷  魏奇  付强  李伟  王世伟 《应用化学》2022,39(9):1321-1344
钙钛矿太阳能电池作为第3代新概念太阳能电池,具有高光电转换效率、低成本和可柔性加工等优点,近年来发展迅速,其光电转换效率从一开始的3.8%增长到近期的25.5%,逐渐比肩硅电池,已接近商业化应用水平。目前,实现钙钛矿太阳能电池产业应用的关键环节在于电池封装,它不仅可以解决钙钛矿光伏器件稳定性问题,还可以实现电池安全、环保和延长使用寿命等要求。结合近十几年来钙钛矿光伏电池封装材料和封装工艺两方面的发展现状,文中介绍了钙钛矿电池封装领域取得的成果和存在的不足,讨论了目前现有封装技术的优缺点,以及它们适用的不同器件类型。着重在不同温度湿度条件下,比较了不同封装材料性能、封装工艺条件对钙钛矿电池效率及稳定性的影响,归纳出影响钙钛矿电池薄膜封装效果的3个关键因素: 聚合物的弹性模量、水蒸气透过率、加工温度。比较了不同聚合物薄膜封装材料适宜的加工温度、优缺点及加工成本。可以看出,随着钙钛矿光伏电池工业化需求的强烈增长和人们对其封装材料研究的不断深入,研究适合大面积生产和光伏建筑一体化的新型功能聚合物封装材料将是必然趋势。  相似文献   
2.
This review article covers the growth and characterization of two-dimensional (2D) crystals of transition metal chalcogenides, h-BN, graphene, etc. The chemical vapor transport method for bulk single crystal growth is discussed in detail. Top-down methods like mechanical and liquid exfoliation and bottom-up methods like chemical vapor deposition and molecular beam epitaxy for mono/few-layer growth are described. The optimal characterization techniques such as optical, atomic force, scanning electron, and Raman spectroscopy for identification of mono/few-layer(s) of the 2D crystals are discussed. In addition, a survey was done for the application of 2D crystals for both creation and deterministic transfer of single-photon sources and photovoltaic systems. Finally, the application of plasmonic nanoantenna was proposed for enhanced solar-to-electrical energy conversion and faster/brighter quantum communication devices.  相似文献   
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《Current Applied Physics》2015,15(4):511-519
The flat a-Si and slanted nanocolumnar (S-nC) a-Si thin films were prepared on c-Si and corning glass substrates by e-beam physical vapor deposition (EB-PVD) technique. The structural properties of all the grown thin films were determined by X-Ray Diffraction (XRD) analysis and Raman spectroscopy. Surface and cross-sectional morphology of a-Si/c-Si and S-nC a-Si/c-Si heterojunctions were investigated by Field Emission Scanning Electron Microscopy (FE-SEM). Sculptured thin films demonstrate potential for significant nanoscale applications in the area of thin film technology. The electrical and photovoltaic properties of these heterojunctions have been investigated by means of dc current–voltage (I–V) measurements at room temperature in dark and light conditions. The S-nC STFs' performance has been found to be improvable on changing the morphology of the thin film. We have found that, the porous morphology of this structure improves the photosensitivity features in photovoltaic devices and solar cell technology. We gained a high open voltage value, such as 900 mV in S-nC a-Si/c-Si thin film, without any doping process.  相似文献   
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Host‐guest encapsulation of functional organic dye into a porous metal‐organic framework can give rise to the development of new functional materials. In this work, by intercalating the stilbazolium‐type dye (DEAST)I (4′‐diethylamino‐N‐methyl stilbazolium) into four lanthanide layered metal‐organic complexes (Ln‐LMOCs), i. e. {[Ln(BTB)(H2O)2]?3(DMF)?2(H2O)}n (Ln=La (1), Nd (2), Sm (3), Er (4)), four responsive (DEAST)I@Ln‐LMOC composites have been prepared, serving as multifunctional performance platform. The core–shell structures of (DEAST)I@Ln‐LMOC composites have been fully characterized by IR, UV/Vis, PXRD, SEM, TEM, TGA and ESR. Significantly, after intercalation of dyes, the (DEAST)I@Ln‐LMOC composites exhibit enhanced luminescent sensing properties in detecting Fe3+ with much higher water stabilities. The luminescent sensing behavior stems from the fluorescence resonance energy transfer (FRET) from the π‐electron‐rich BTB ligands to the Fe3+, and their higher water stabilities are induced by electrostatic interactions and lower porosity. Specially, the characteristic emissions of Sm3+ will not be affected after the encapsulation guest dyes, which provide a theoretical guide for the modulation of luminescence devices. Finally, better ion conductivities and diminished photocurrents can be achieved after the embedding of the functional organic dye. In all, the formation of (DEAST)I@Ln‐LMOC composites with core–shell structures can be utilized as a multifunctional platform with good stability.  相似文献   
7.
Al-doped ZnO rods of nanometer to sub-micrometer size range have been successfully synthesized by a simple yet cost-effective solution processed sonochemical technique. Systematic XRD analysis established the solid solubility limit for Al in the ZnO lattice to be ca. 3 mol% at an elevated annealing temperature of 800 °C. The secondary ZnAl2O4 phase appears with increasing dopant concentrations and at lower annealing temperatures. Significant variations in the optoelectronic properties are induced by modifications in the surface defects of ZnO rods as a result of Al doping. As a consequence, an improved fill factor (FF) of 74.78 and 75.76% with a conversion efficiency (η) of 1.59 and 1.79% have been achieved for the fabricated DSSC devices made of the 800 °C annealed ZnO rods doped by 1 and 3 mol% Al, respectively.  相似文献   
8.
The present study involves fabrication and photovoltaic characterization including impedance properties of dye-sensitized solar cells based on natural dye from beetroot. The electrode of the cell was prepared with commercial Fluorine-doped Tin Oxide glass with 100 μm layer of nanostructured TiO2 whereas, the counter electrode consisted of platinum-coated glass. Fresh juice was extracted from beetroot to use as dye. The dye exhibited high absorption in visible range. Photovoltaic measurements of the solar cell gave a short circuit current density (Jsc) of 130 μA/cm2 and an open-circuit voltage (VOC) of 0.38 V under AM 1.5 illumination intensity. The VOC and Jsc showed linear behavior at higher values of illumination intensities. The conductance-voltage, the capacitance-voltage and the series resistance voltage characteristics of the dye solar cell was measured at frequency range from 5 kHz to 5 MHz to study performance of the dye-sensitized solar cells with natural dyes.  相似文献   
9.
Based on the method of in situ polymerization synthesis combined with two-step sinter-ing process, LiFe1-xVx(PO4)(3-y)/3Fy/C was prepared. The e ects of V and F co-doping on the structure, morphology, and electrochemical performances of LiFePO4/C were in-vestigated by X-ray di raction, Fourier transform infrared spectra, scanning electron mi-croscope, charge/discharge tests, and electrochemical impedance spectroscopy, respectively. The results indicated that the V and F co-doping did not destroy the olivine structure of LiFePO4/C, but it can stabilize the crystal structure, decrease charge transfer resistance, enhance Li ion di usion velocity, further improve its cycling and high-rate capabilities of LiFePO4/C.  相似文献   
10.
In this work, we demonstrate a novel synthesis of synthetic rutile from high titanium slag. This rutile TiO2 was obtained by a simple one-step microwave roasting route. The influence of microwave roasting temperature and duration on the phase transformation of high titanium slag has been assessed. X-ray diffraction (XRD) results indicate that the intensity of anosovite (Fe3Ti3O10) phase, which were the major phase of high titanium slag of carbon thermal reduction of ilmenite ores, decreased rapidly while the peaks for rutile TiO2 phase increased with increase in the microwave roasting temperature. The scanning electron microscope (SEM) images revealed formation and the particle-size distribution of rutile TiO2 phase. Based on XRD and SEM analysis, confirmed the dependence of phase structure, composition and crystallite size on the process conditions of microwave roasting.  相似文献   
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