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51.
Jinhua Gao Yuanfang Tao Dr. Jian Zhang Nannan Wang Xin Ji Dr. Jinling He Prof. Yubing Si Prof. Weili Zhao 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(48):11246-11256
Our previous discovery suggested that substituents on the 1,7 positions delicately modulate the sensing ability of the meso-arylmercapto boron-dipyrromethene (BODIPY) to biothiols. In this work, the impact of delicate modulations on the sensing ability is investigated. Therefore, 1,7-dimethyl, 3,5-diaryl substituted BODIPY is designed and developed and its conformationally restricted species with a meso-arylmercapto moiety ( DM-BDP-SAr and DM-BDP-R-SAr ) as selective fluorescent probes for Cys. Moreover, the lysosome-target probes ( Lyso-S and Lyso-D ) based on DM-BDP-SAr carrying one or two morpholinoethoxy moieties were developed. They were able to detect Cys selectively in vitro with low detection limits. Both Lyso-S and Lyso-D localized nicely in lysosomes in living HeLa cells and exhibited red fluorescence for Cys. Moreover, a novel fluorescence quenching mechanism was proposed from the calculations by density functional theory (DFT). The probes may go through intersystem crossing (from singlet excited state to triplet excited state) to result in fluorescence quenching. 相似文献
52.
Flexible control of building blocks of photonic crystals enables achieving desirable band structures. Exploration of photonic band extrema has brought many fantastic features to design artificial optical materials, such as Brillouin‐zone‐corner extrema for valley photonic materials and zone‐center extremum for zero‐index metamaterials. However, two such kinds of extrema are always found independently in different photonic crystals. In this work, a kind of valley photonic crystals possessing both zone‐center and zone‐corner band extrema almost at the same frequency is proposed. Inspired by antennas theory, a three‐antenna array (TAA) source is devoted to individually manipulate each extremum. The correlation coefficient is given to determine the coupling efficiency between the TAA source and extrema eigenmodes. By using a source with a high correlation coefficient, these extrema bulk states are selectively excited consistent with their eigenfields. Furthermore, three control cases are shown that multiple extrema points are simultaneously excited, in order to confirm the validity of the correlation coefficient. Finally, a potential application of a beam‐steering device is proposed through selective excitation of ternary extrema. This work develops binary valley states into ternary mix states, rendering more degrees of freedom for on‐chip optical information transport, particularly for beam steering and mode division multiplexing. 相似文献
53.
Daliao Tao Zhiqin Wang Xiaoyu Huang Mingwei Tian Guolin Lu Ian Manners Mitchell A. Winnik Chun Feng 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(21):8309-8316
Fiber-like π-conjugated nanostructures are important components of flexible organic electronic and optoelectronic devices. To broaden the range of potential applications, one needs to control not only the length of these nanostructures, but the introduction of diverse functionality with spatially selective control. Here we report the synthesis of a crystalline-coil block copolymer of oligo(p-phenylenevinylene)-b-poly(2-vinylpyridine) (OPV5-b-P2VP44), in which the basicity and coordinating/chelating ability of the P2VP segment provide a landscape for the incorporation of a variety of functional inorganic NPs. Through a self-seeding strategy, we were able to prepare monodisperse fiber-like micelles of OPV5-b-P2VP44 with lengths ranging from 50 to 800 nm. Significantly, the exposed two ends of OPV core of these fiber-like micelles remained active toward further epitaxial deposition of OPV5-b-PNIPAM49 and OPV5-b-P2VP44 to generate uniform A-B-A and B-A-B-A-B segmented block comicelles with tunable lengths for each block. The P2VP domains in these (co-)micelles can be selectively decorated with inorganic and polymeric nanoparticles as well as metal oxide coatings, to afford hybrid fiber-like nanostructures. This work provides a versatile strategy toward the fabrication of narrow length dispersity continuous and segmented π-conjugated OPV-containing fiber-like micelles with the capacity to be decorated in a spatially selective way with varying functionalities. 相似文献
54.
随着能源紧缺与环境污染问题的日益严重,太阳能的开发利用越来越受到重视,其中非晶硅薄膜太阳能电池由于其制备工艺简单、价格低廉等优点被广泛地研究.为了使非晶硅薄膜太阳能电池得到更好地利用,提高其转换效率和稳定性显得尤为重要.引入复合背电极是提高非晶硅太阳能电池性能的有效手段,其中对GZO/Al复合背电极的研究还未见报道.在该工作中,利用磁控溅射法在非晶硅电池上制备了GZO/Al复合背电极,研究了复合背电极的制备条件及其对非晶硅太阳能电池性能的影响.结果显示,当GZO层的溅射功率为90 W、Al层的溅射功率为90 W时,具有复合背电极的太阳能电池表现出较好的光电转换性能,其短路电流(ISC)、开路电压(VOC)、填充因子(FF)和电池的光电转换效率(η)分别为8.92 mA、1.55 V、54.48;和7.53;.相较于单层Al背电极的太阳能电池,其光电转换效率大幅提高了47.6;(相对效率). 相似文献
55.
Dr. Qing Xu Dr. Shanshan Tao Dr. Qiuhong Jiang Prof. Donglin Jiang 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(11):4587-4593
A strategy based on covalent organic frameworks for ultrafast ion transport involves designing an ionic interface to mediate ion motion. Electrolyte chains were integrated onto the walls of one-dimensional channels to construct ionic frameworks via pore surface engineering, so that the ionic interface can be systematically tuned at the desired composition and density. This strategy enables a quantitative correlation between interface and ion transport and unveils a full picture of managing ionic interface to achieve high-rate ion transport. Moreover, the effect of interfaces was scaled on ion transport; ion mobility is increased in an exponential mode with the ionic interface. This strategy not only sets a benchmark system but also offers a general guidance for designing ionic interface that is key to systems for energy conversion and storage. 相似文献
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58.
Regulation of Charge Delocalization in a Heteronuclear Fe2Ru System by a Stepwise Photochromic Process 下载免费PDF全文
Guang‐Tao Xu Dr. Bin Li Dr. Jin‐Yun Wang Dr. Dao‐Bin Zhang Prof. Zhong‐Ning Chen 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(8):3318-3326
Heteronuclear complexes FeCp2?DTE?C?C?Ru(dppe)2Cl ( 1 o ; dppe=1,2‐bis(diphenylphosphino)ethane, Cp=cyclopentadienyl, DTE=dithienylethene) and FeCp2?DTE?C?C?Ru(dppe)2?C?C?DTE?FeCp2 ( 2 oo ), with redox‐active ferrocenyl and ruthenium centers separated by a photochromic DTE moiety, were prepared to achieve photoswitchable charge delocalization and Fe???Ru electronic communication. Upon UV‐light irradiation of 2 oo , the Fe???Ru heterometallic electronic interaction is increasingly facilitated with stepwise photocyclization, 2 oo → 2 co → 2 cc ; this is ascribed to the gradual increase in π‐conjugated systems. The near‐infrared absorptions in mixed‐valence species [ 2 oo ]+/[ 2 co ]+/[ 2 cc ]+ are gradually intensified following the conversion of [ 2 oo ]+→[ 2 co ]+→[ 2 cc ]+, which demonstrates that the extent of charge delocalization shows progressive enhancement with stepwise photocyclization. As revealed by electrochemical, spectroscopic, and theoretical studies, complex 2 exhibits nine switchable states through stepwise photochromic and reversible redox processes. 相似文献
59.
Organic electrode materials (OEMs) are being investigated as promising candidates for aqueous zinc-ion batteries (AZIBs) owing to their environmental friendliness, cost-effectiveness, and structural diversity, and tunability. Understanding the correlation between structural regulation of OEMs and their electrochemical property in AZIBs is vital to rational design of OEMs. Herein, we first discuss the fundamentals of the energy storage mechanism of OEMs. Then, strategies to improve the electrochemical performance, including the specific capacity, voltage, rate capability, and cycling stability, are elaborated from the perspective of molecular engineering. Finally, we share our views on the remaining challenges and prospects of OEMs in AZIBs. 相似文献
60.
碲锰镉(CdMnTe)作为性能优异的室温核辐射探测器材料,可用于环境监测和工业无损检测领域。本文中采用Te溶剂Bridgman法生长In掺杂Cd0.9Mn0.1Te晶体,制备成10 mm×10 mm×2 mm大小的室温单平面探测器,研究了该探测器对241Am@59.5 keV γ射线源的能谱响应。通过表征红外透过率、电阻率以及探测器能谱响应等参数,综合评定了探测器用CdMnTe晶体的质量、电学和探测器性能。结果表明,晶片的红外透过率均在55%以上,最好可达到60%。采用湿法钝化,100 V偏压下的漏电流由钝化前的9.48 nA降为钝化后的7.90 nA,钝化后的电阻率为2.832×1010 Ω·cm。在-400 V反向偏压下,CdMnTe探测器对241Am@59.5 keV γ射线源的能量分辨率在钝化前后分别为13.53%和12.51%,钝化后的电子迁移率寿命积为1.049×10-3 cm2/V。研究了探测器的能量分辨率随电压的变化特性,当偏压≤400 V时,探测器的能量分辨率主要由载流子的收集效率决定,而当偏压>400 V时,能量分辨率由漏电流决定。本文研究结果表明,Te溶剂Bridgman法生长的CdMnTe晶体质量较好,电阻率和电子迁移率寿命积满足探测器制备需求。 相似文献