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101.
Mei Yang Kean Chen Hui Li Yuliang Cao Hanxi Yang Xinping Ai 《Advanced functional materials》2023,33(47):2306828
Many organic solvents have excellent solution properties, but fail to serve as lithium-ion batteries (LIBs) electrolyte solvents, due to their electrochemical incompatibility with graphite anodes. Herein, a new strategy is proposed to address this issue by introducing a surface-adsorbed molecular layer to regulate the interfacial solvation structure without the alteration of electrolyte composition and properties. As a proof-of-concept study, it is demonstrated for the first time that the intrinsically incompatible propylene carbonate (PC)-based electrolyte becomes completely compatible with graphite anodes by introducing a layer of adsorbed hexafluorobenzene (HFB) molecules to weaken the Li+-PC coordination strength and facilitate the interfacial desolvation process. As a consequence, the graphite/ NCM811 pouch cells using the PC-based electrolyte containing only 1 vol.% HFB demonstrate excellent long-term cycling stabilities over 1150 cycles. This strategy is also proved to be applicable to other ethylene carbonate (EC)–free electrolytes, thus providing a new avenue for developing advanced LIB electrolytes. 相似文献
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光电跟踪系统力矩波动干扰抑制的研究 总被引:2,自引:1,他引:2
光电跟踪系统的力矩波动是影响其跟踪精度的噪声的角度一个关键问题.基于某光电跟踪控制系统动态模型,从抑制噪声的角度分析了加入电流环对抑制力矩波动的影响,同时还分析了系统速度、电流两环闭环带宽与力矩波动抑制之间的关系.分析表明,加入电流环后的光电跟踪系统抑制力矩波动的能力明显增强,同时较高的速度回路带宽有利于抑制力矩波动引起的干扰,且在速度带宽一定的情况下增加电流用环带宽对抑制力矩波动也有一定作用.因此,在设计光电跟踪系统时,在不影响系统稳定性的前提下应选用尽可能大的速度及电流闭环带宽. 相似文献
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回顾了电力电子器件的发展历程,对各种电力电子器件的原理、特性以及在电力电子装置中的应用进行了比较分析,最后对电力电子器件的发展前景进行了展望。 相似文献
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High‐κ Solid‐Gate Transistor Configured Graphene Biosensor with Fully Integrated Structure and Enhanced Sensitivity 下载免费PDF全文
Cheng Wang Yijun Li Yibo Zhu Xiaohong Zhou Qiao Lin Miao He 《Advanced functional materials》2016,26(42):7668-7678
A fully integrated graphene field‐effect transistor (GFET) nanosensor utilizing a novel high‐κ solid‐gating geometry for a practical biosensor with enhanced sensitivity is presented. Herein, an “in plane” gate supplying electrical field through a 30 nm HfO2 dielectric layer is employed to eliminate the cumbrous external wire electrode in conventional liquid‐gate GFET nanosensors that undesirably limits the device potential in on‐site sensing applications. In addition to the advantage in the device integration degree, the transconductance level is found to be increased by about 50% over liquid‐gate GFET devices in aqueous‐media, thereby improves the sensitivity performance in sensor applications. As the first demonstration of biosensing applications, a small‐molecule antibiotic, kanamycin A, is detected by means of an aptameric competitive affinity principle. It is experimentally shown that the label‐free and specific quantification of kanamycin A with a concentration resolution at 11.5 × 10?9 m is achievable through a single direct observation of the 200 s fast bioassay without any further noise canceling. These results demonstrate the utility and practicability of the new devices in label‐free biosensing as a novel analytical tool, and potentially hold great promise in other significant biomedical applications. 相似文献
107.
Youngseok Lee Vinh Ai Dao S. M. Iftiquar Sangho Kim Junsin Yi 《Progress in Photovoltaics: Research and Applications》2016,24(1):52-58
This paper presents an understanding of the fundamental carrier transport mechanism in hydrogenated amorphous silicon (a‐Si:H)‐based n/p junctions. These n/p junctions are, then, used as tunneling and recombination junctions (TRJ) in tandem solar cells, which were constructed by stacking the a‐Si:H‐based solar cell on the heterojunction with intrinsic thin layer (HIT) cell. First, the effect of activation energy (Ea) and Urbach parameter (Eu) of n‐type hydrogenated amorphous silicon (a‐Si:H(n)) on current transport in an a‐Si:H‐based n/p TRJ has been investigated. The photoluminescence spectra and temperature‐dependent current–voltage characteristics in dark condition indicates that the tunneling is the dominant carrier transport mechanism in our a‐Si:H‐based n/p‐type TRJ. The fabrication of a tandem cell structure consists of an a‐Si:H‐based top cell and an HIT‐type bottom cell with the a‐Si:H‐based n/p junction developed as a TRJ in between. The development of a‐Si:H‐based n/p junction as a TRJ leads to an improved a‐Si:H/HIT‐type tandem cell with a better open circuit voltage (Voc), fill factor (FF), and efficiency. The improvements in the cell performance was attributed to the wider band‐tail states in the a‐Si:H(n) layer that helps to an enhanced tunneling and recombination process in the TRJ. The best photovoltage parameters of the tandem cell were found to be Voc = 1430 mV, short circuit current density = 10.51 mA/cm2, FF = 0.65, and efficiency = 9.75%. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
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