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71.
Organic-inorganic lead halide perovskite solar cells have captured significant attention in recent years due to low processing costs and unprecedented development in power conversion efficiency (PCE). It has appeared from 2009 with PCE of 3.8% to being claimed more than 25.2% PCE in a very short span of time, showing their future prospective toward the fabrication of less expensive and stable solar cells. The incredible advancement in this technology encourages at one end, whereas several hurdles restricting its complete utilization for commercial purposes at another end. Although the selection of perovskite structure is limited with planar and mesoporous electron transport layers (ETLs), but identification of appropriate ETLs necessitates excellent effort to improve the surface morphology of absorber and obtain enhanced PCE with higher stability. In the present review, we have investigated various inorganic-organic ETLs with different device configurations of PSCs, primarily focusing on crystallization and morphology control techniques of ETL thin films. Numerous strategies such as surface functionalization, doping, and addition of interfacial layer are adopted for ETLs, and their effect on device efficiency, performance, and hysteresis is also discussed in detail. Additionally, designs of PSCs with different device configurations are discussed as well, providing future guidelines for significant progress in PSCs structure with different ETLs. 相似文献
72.
Vesicle Structures from Bolaamphiphilic Biosurfactants: Experimental and Molecular Dynamics Simulation Studies on the Effect of Unsaturation on Sophorolipid Self‐Assemblies
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Prabhu Dhasaiyan Prithvi Raj Pandey Nikunjkumar Visaveliya Dr. Sudip Roy Dr. B. L. V. Prasad 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(21):6246-6250
The formation of giant‐vesicle‐like structures by self‐assembling linolenic acid sophorolipid (LNSL) molecules is revealed. Sophorolipids belong to the class of bolaamphiphilic glycolipid biosurfactants. Interestingly, the number of double bonds present in the hydrophobic core of sophorolipids is seen to have a great influence on the type of self‐assembled structures formed. Dye encapsulation results establish the presence of an aqueous compartment inside the LNSL vesicles. Molecular dynamics simulation (MD) studies suggest the existence of two possible conformations of LNSLs inside the self‐assembled structures and that LNSL molecules arrange in layered structures. 相似文献
73.
A. Moses Ezhil Raj V.S. Vidhya A. Thayumanavan C. Sanjeeviraja 《Physica B: Condensed Matter》2008,403(4):544-554
Thin films of indium oxide, In2O3, were deposited by chemical spray pyrolysis technique, using aqueous alcoholic solutions of indium acetylacetonate (In-acac) precursor, on glass substrates kept at temperatures between 300 and 500 °C. The structural, optical, and electrical properties have been investigated as a function of deposition temperature, precursor concentration, carrier gas pressure, and substrate-to-nozzle distance. X-ray diffraction studies showed that the formation of nanocrystalline In2O3 films is preferentially oriented along (2 2 2) plane. The surface morphological modifications with substrate temperature were observed using scanning electron and atomic force microscopic studies. Optical transmittance behavior of the films in the visible and IR region was strongly affected by the deposition parameters. The optical band gap values observed are between 3.53 and 3.68 eV. The long wavelength limit of refractive index is 1.83. The Hall mobility is found to vary from 23 to 37 cm2/V s and carrier density is found nearly constant at about 1020 cm−3. 相似文献
74.
Borole Abhijeet P. Sublette Kerry L. Fisher J. Berton Raterman Kevin T. Kemp Nan P. McInerney Michael J. 《Applied biochemistry and biotechnology》1996,57(1):817-826
Applied Biochemistry and Biotechnology - The addition of gas condensate hydrocarbons to saturated soil from a gas production site stimulated sulfate reduction under anaerobic and oxygen-limiting... 相似文献
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The MgO (2 0 0) surface is widely used as a substrate for epitaxial growth of superconducting and ferro-electric films. Highly oriented, single crystalline, extremely flat and transparent MgO films have been successfully deposited on quartz substrates by the chemical spray pyrolysis technique using economically viable metal organic and inorganic precursors under optimized conditions at the substrate temperature of 600 °C. Thermal analysis (TGA/DTA) in the temperature range 30-600 °C with the heating rate of 10 °C/min revealed the decomposition behavior of the precursors and confirmed the suitable substrate temperature range for film processing. The heat of reaction, ΔH due to decomposition of metal organic precursor contributed additional heat energy to the substrate for better crystallization. The intensity of the (2 0 0) peak in X-ray diffraction (XRD) measurements and the smooth surface profiles revealed the dependency of precursor on film formation. The compositional purity and the metal-oxide bond formation were tested for all the films. UV-Vis-NIR optical absorption in the 200-1500 nm range revealed an optical transmittance above 80% and the absorption edge at about 238 nm corresponding to an optical band gap Eg = 5.25 eV. Scanning electron microscopy (SEM) and atomic force microscopy (AFM) micrographs of MgO films confirmed better crystallinity with larger grain size (0.85 μm) and reduced surface roughness (26 nm), respectively. 相似文献
77.
D.M. Raj KumarM. Manivel Raja K. PrabaharV. Chandrasekaran Asok PoddarR. Ranganathan K.G. Suresh 《Journal of magnetism and magnetic materials》2011,323(13):1750-1754
The effect of Si/Ge ratio on resistivity and thermopower behavior has been investigated in the magnetocaloric ferromagnetic Gd5SixGe4−x compounds with x=1.7-2.3. Microstructural studies reveal the presence of Gd5(Si,Ge)4-matrix phase (5:4-type) along with traces of secondary phases (5:5 or 5:3-type). The x=1.7 and 2.0 samples display the presence of a first order structural transition from orthorhombic to monoclinic phase followed by a magnetic transition of the monoclinic phase. The alloys with x=2.2 and 2.3 display only magnetic transitions of the orthorhombic phase. A low temperature feature apparent in the AC susceptibility and resistivity data below 100 K reflects an antiferromagnetic transition of secondary phase(s) present in these compounds. The resistivity behavior study correlates with microstructural studies. A large change in thermopower of −8 μV/K was obtained at the magneto-structural transition for the x=2 compound. 相似文献
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S. Shanmuga Sundara Raj Hoong‐Kun Fun Zhong‐Lin Lu Wen Xiao Xiao‐Yang Gong Chang‐Ming Gen 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(8):1013-1014
The crystal structure of the title compound, C15H14N2O2·H2O, is in the keto tautomeric form and the configuration at the azomethine C=N double bond is E. The molecule is non‐planar, with a dihedral angle of 27.3 (1)° between the aromatic rings. The crystal structure is stabilized by extensive hydrogen bonding involving the water molecule and hydrazone moiety. 相似文献