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31.
Nanotextured multicrystalline Al‐BSF solar cells reaching 18% conversion efficiency using industrially viable solar cell processes
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Bishal Kafle Abdul Mannan Timo Freund Laurent Clochard Edward Duffy Marc Hofmann Jochen Rentsch Ralf Preu 《固体物理学:研究快报》2015,9(8):448-452
We report recent achievements in adapting industrially used solar cell processes on nanotextured surfaces. Nanostructures were etched into c‐Si surfaces by dry exothermic plasma‐less reaction of F species with Si in atmospheric pressure conditions and then modified using a short post‐etching process. Nanotextured multicrystalline wafers are used to prepare Al‐BSF solar cells using industrially feasible solar cell proc‐ essing steps. In comparison to the reference acidic textured solar cells, the nanostructured cells showed gain in short circuit current (Jsc) of up to 0.8 mA/cm2 and absolute gain in conversion efficiency of up to 0.3%. The best nanotextured solar cell was independently certified to reach the conversion efficiency of 18.0%. (© 2015 WILEY‐VCH Verlag GmbH &Co. KGaA, Weinheim) 相似文献
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Dr. Dmitry Katayev Kai F. Pfister Timo Wendling Prof. Dr. Lukas J. Gooßen 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(32):9902-9905
Various (hetero)arenecarboxylic acids were converted to the corresponding Daugulis amides and nitrated selectively in the ortho‐position in the presence of [CuNO3(PPh3)2] and AgNO2 at 50 °C. A microwave‐assisted saponification allows regenerating the carboxylate group within minutes, which may then be removed tracelessly by protodecarboxylation, or substituted by aryl‐ or alkoxy‐groups via decarboxylative cross‐coupling. 相似文献
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Timo Marks Prof. Dr. Ewald Daltrozzo Prof. Dr. Andreas Zumbusch 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(21):6494-6504
The reaction of POCl3‐activated, readily soluble diketopyrrolopyrrole (DPP) with 2‐aminoheteroaromatics to yield 1:1 and 1:2 hydrogen chelates is described. Complexation of these hydrogen chelates with boron reagents results in thermally and photochemically stable fluorescent dyes (PP–azacyanines). The 1:2 complexes in particular absorb at long wavelengths and are brightly fluorescing. The rich photophysics of the new compounds are presented. Both the pronounced vibrational fine structure of the S0→S1 transitions and the observed fluorescence phenomena allow detailed conclusions to be made on the correlation between molecular structure and optical properties. 相似文献
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M. Sc. Timo Trageser Dr. Michael Bolte Dr. Hans-Wolfram Lerner Prof. Dr. Matthias Wagner 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(20):7800-7805
The tetraaryl μ-hydridodiborane(4) anion [ 2 H]− possesses nucleophilic B−B and B−H bonds. Treatment of K[ 2 H] with the electrophilic 9-H-9-borafluorene (HBFlu) furnishes the B3 cluster K[ 3 ], with a triangular boron core linked through two BHB two-electron, three-center bonds and one electron-precise B−B bond, reminiscent of the prominent [B3H8]− anion. Upon heating or prolonged stirring at room temperature, K[ 3 ] rearranges to a slightly more stable isomer K[ 3 a ]. The reaction of M[ 2 H] (M+=Li+, K+) with MeI or Me3SiCl leads to equimolar amounts of 9-R-9-borafluorene and HBFlu (R=Me or Me3Si). Thus, [ 2 H]− behaves as a masked [:BFlu]− nucleophile. The HBFlu by-product was used in situ to establish a tandem substitution-hydroboration reaction: a 1:1 mixture of M[ 2 H] and allyl bromide gave the 1,3-propylene-linked ditopic 9-borafluorene 5 as sole product. M[ 2 H] also participates in unprecedented [4+1] cycloadditions with dienes to furnish dialkyl diaryl spiroborates, M[R2BFlu]. 相似文献
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Damping in air gaps of micromechanical devices that vibrate out-of-plane is studied at frequencies where the acoustic wavelength is comparable with the air gap dimensions. A FEM study with a viscoacoustic solver shows that above a certain frequency, closed damper borders can be assumed in the approximate analysis of the squeeze-film damper, regardless of the practical border conditions. Here, this closed-border (trapped gas) problem is solved analytically from the linearized Navier–Stokes equations in 1D. This results in a compact model for the mechanical impedance that accounts for damping, inertial and spring forces as well as thermal behaviour and slip border conditions. The model produces the gas resonances in the air gap when the wavelength of the acoustic wave is smaller than the gap dimensions. Due to the slip conditions, the model is valid in modeling micromechanical oscillating structures with small air gaps. 相似文献
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