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961.
Chen Sun Ya‐Hui Guo Sha‐Sha Han Jing‐Zhao Li Kuan Jiang Lin‐Feng Dong Qi‐Long Liu Cheng‐Yang Yue Xiao‐Wu Lei 《Angewandte Chemie (International ed. in English)》2020,59(38):16465-16469
Considering the instability and low photoluminescence quantum yield (PLQY) of blue‐emitting perovskites, it is still challenging and attractive to construct single crystalline hybrid lead halides with highly stable and efficient blue light emission. Herein, by rationally introducing d10 transition metal into single lead halide as new structural building unit and optical emitting center, we prepared a bimetallic halide of [(NH4)2]CuPbBr5 with new type of three‐dimensional (3D) anionic framework. [(NH4)2]CuPbBr5 exhibits strong band‐edge blue emission (441 nm) with a high PLQY of 32 % upon excitation with UV light. Detailed photophysical studies indicate [(NH4)2]CuPbBr5 also displays broadband red light emissions derived from self‐trapped states. Furthermore, the 3D framework features high structural and optical stabilities at extreme environments during at least three years. To our best knowledge, this work represents the first 3D non‐perovskite bimetallic halide with highly efficient and stable blue light emission. 相似文献
962.
963.
Qing Shao Shaodong Zhang Zhen Hu Yongfeng Zhou 《Angewandte Chemie (International ed. in English)》2020,59(39):17125-17129
Engineering synthetic materials that mimic the complex rhythmic oscillatory behavior of living cells is a fundamental challenge in science and technology. Up to now, the reported synthetic model system still cannot compete with nature in oscillatory modes and amplitudes. Presented here is a novel alternating copolymer vesicle that exhibits drastic and multimode shape oscillations in real time, which are controlled by polymer concentrations and driven by the Belousov—Zhabotinsky oscillatory reaction, including swelling/deswelling, twisting/detwisting, stretching/shrinking, fusion/fission, and multiple division. Some of them, especially the fission oscillation, have not been observed before. In addition, the oscillation magnitude with regard to diameter is much larger than that of previously reported self‐oscillating vesicles. Such a self‐oscillating vesicle transformer would extend the complexity and capacity of membrane deformations in synthetic systems, approaching those of natural cells. 相似文献
964.
965.
Covalent organic frameworks (COFs) as an emerging type of crystalline porous materials, have obtained considerable attention recently. They have exhibited diverse structure and attractive performance in various catalytic reactions. It is highly expected to have a systematic and comprehensive review summing up COFs‐derived catalysts in homogeneous and heterogeneous catalysis, which is favorable to the judicious design of an efficient catalyst for targeted reaction. Herein, we focus on summarizing recent and significant developments in COFs materials, with an emphasis on both the synthetic strategies and targeted functionalization, and categorize it in accordance with the different types of catalytic reactions. Their potential catalysis applications are reviewed thoroughly. Moreover, a personal view about the future development of COFs catalysts with respect to the large‐scale production is also discussed. 相似文献
966.
Coupled Electrical Conduction in Coordination Polymers: From Electrons/Ions to Mixed Charge Carriers
The coupled transport of ions and electrons is of great potential for next‐generation sensors, energy storage and conversion devices, optoelectronics, etc. Coordination polymers (CPs) intrinsically have both transport pathways for electrons and ions, however, the practical conductivities are usually low. In recent years, significant advances have been made in electronic or ionic conductive coordination polymers, which also results in progress in mixed ionic‐electronic conductive coordination polymers. Here we start from electronic and ionic conductive CPs to mixed ionic‐electronic conductive CPs. Recent advances in the design of mixed ionic‐electronic conductive CPs are summarized. In addition, devices based on mixed conduction are selected. 相似文献
967.
968.
《Particuology》2022
Natural systems are typically featured with tremendous molecular complexity and construct exquisite architectures and functional materials through precise spatial and temporal control. Supramolecular self-assembly from peptides and proteins is believed to be the key player. Thus, knowledge of the fundamental mechanisms driving peptides into vast functional hierarchical structures will certainly help the rational control of self-assembly process, leading to more precise structural organization and functional optimization. In this review, we briefly summarize the recent progress of this burgeoning field mainly from two directions: peptide-based self-assembly and co-assembly with other functional molecules, each part is further divided into two subparts and representative examples are given for each subpart according to their development timeline. At the end of each part, brief summaries of the closely related applications are outlined. For the closing remarks, we conclude with our own understanding of the area and perspectives are given based on recent developments. Overall, this review could be suitable for both new readers to gain a comprehensive overview of the area and experienced readers to get a summary of the development in short peptide self-assembly from particles to functional materials. 相似文献
969.
Liang-sheng Duan Quan-ping Wu Yuan-yuan Xu Hui Wang Zhe Sun Yu Chen Song Xue 《化学物理学报(中文版)》2021,34(2):217-226
Four organic small-molecule hole transport materials ( D41 , D42 , D43 and D44 ) of tetraarylpyrrolo[3, 2-b]pyrroles were prepared. They can be used without doping in the manufacture of the inverted planar perovskite solar cells. Tetraarylpyrrolo[3, 2-b]pyrroles are accessible for one-pot synthesis. D42 , D43 and D44 possess acceptor-\begin{document}$ \pi $\end{document} -donor-\begin{document}$ \pi $\end{document} -acceptor structure, on which the aryl bearing substitutes of cyan, fluorine and trifluoromethyl, respectively. Instead, the aryl moiety of D41 is in presence of methyl with a donor-\begin{document}$ \pi $\end{document} -donor-\begin{document}$ \pi $\end{document} -donor structure. The different substitutes significantly affected their molecular surface charge distribution and thin-film morphology, attributing to the electron-rich properties of fused pyrrole ring. The size of perovskite crystalline growth particles is affected by different molecular structures, and the electron-withdrawing cyan group of D42 is most conducive to the formation of large perovskite grains. The D42 fabricated devices with power conversion efficiency of 17.3% and retained 55% of the initial photoelectric conversion efficiency after 22 days in dark condition. The pyrrolo[3, 2-b]pyrrole is efficient electron-donating moiety for hole transporting materials to form good substrate in producing perovskite thin film.
相似文献
970.
气相色谱-质谱法测定电子电气产品中多溴二苯醚及多溴联苯 总被引:14,自引:0,他引:14
建立了利用气相色谱-质谱测定电子、电气产品中多溴二苯醚及多溴苯的方法。对样品的粉碎、提取方法、色谱柱的选择、测定条件进行研究,并自建标准质谱图库;采用保留时间、Br同位素规则、质谱特征离子、谱库检索等4种方式相结合进行定性,避免了假阳性及漏检的情况,结果更加准确可靠。本法检出限为5mg/kg,PBDEs的回收率为91.3%,PBBs的回收率为92.5%,相对标准偏差(RSD)为4.3%。与现有方法相比,本法分离时间最短(6min),具有简便快速、实用性强、灵敏度高、准确可靠等特点,适用于电子电气产品、塑料、橡胶、汽车内饰材料等的溴系阻燃剂分析,满足欧盟RoHS指令检测的要求。 相似文献