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991.
Lei Jiang Haizhen Ding Siyu Lu Ting Geng Guanjun Xiao Bo Zou Hong Bi 《Angewandte Chemie (International ed. in English)》2020,59(25):9986-9991
Photoactivation in CdSe/ZnS quantum dots (QDs) on UV/Vis light exposure improves photoluminescence (PL) and photostability. However, it was not observed in fluorescent carbon quantum dots (CDs). Now, photoactivated fluorescence enhancement in fluorine and nitrogen co‐doped carbon dots (F,N‐doped CDs) is presented. At 1.0 atm, the fluorescence intensity of F,N‐doped CDs increases with UV light irradiation (5 s–30 min), accompanied with a blue‐shift of the fluorescence emission from 586 nm to 550 nm. F,N‐doped CDs exhibit photoactivated fluorescence enhancement when exposed to UV under high pressure (0.1 GPa). F,N‐doped CDs show reversible piezochromic behavior while applying increasing pressure (1.0 atm to 9.98 GPa), showing a pressure‐triggered aggregation‐induced emission in the range 1.0 atm–0.65 GPa. The photoactivated CDs with piezochromic fluorescence enhancement broadens the versatility of CDs from ambient to high‐pressure conditions and enhances their anti‐photobleaching. 相似文献
992.
Hongfeng Li Peng Wu Yawen Xiao Meng Shao Yu Shen Yun Fan Huanhuan Chen Ruijie Xie Wenlei Zhang Sheng Li Jiansheng Wu Yu Fu Bing Zheng Weina Zhang Fengwei Huo 《Angewandte Chemie (International ed. in English)》2020,59(12):4763-4769
Metal–organic frameworks (MOFs) are promising materials with fascinating properties. Their widespread applications are sometimes hindered by the intrinsic instability of frameworks. However, this instability of MOFs can also be exploited for useful purposes. Herein, we report the use of MOFs as metal ion precursors for constructing functional nanocomposites by utilizing the instability of MOFs. The heterogeneous growth process of nanostructures on substrates involves the release of metal ions, nucleation on substrates, and formation of a covering structure. Specifically, the synthesized CoS with carbon nanotubes as substrates display enhanced performance in a lithium‐ion battery. Such strategy not only presents a new way for exploiting the instability of MOFs but also supplies a prospect for designing versatile functional nanocomposites. 相似文献
993.
Shan Jin Manman Zhou Xi Kang Xiaowu Li Wenjun Du Xiao Wei Shuang Chen Shuxin Wang Manzhou Zhu 《Angewandte Chemie (International ed. in English)》2020,59(10):3891-3895
The high‐dimensional (that is, three‐dimensional (3D)) assembly of nanomaterials is an effective means of improving their properties; however, achieving this assembly at the atomic level remains challenging. Herein, we obtained a novel nanocluster, [Au8Ag57(Dppp)4(C6H11S)32Cl2]Cl (Dppp=1,3‐bis(diphenylphosphino)propane) showing a 3D octameric assembly mode involving the kernel penetration of eight complete icosahedral Au@Ag10Au2 units for the first time. The atomically precise structure was determined by single‐crystal X‐ray diffraction, and further confirmed by thermogravimetric analysis, X‐ray photoelectron spectroscopy, and electrospray ionization mass spectrometry measurements. Furthermore, ligand‐induced transformation prompted the conversion of [Au8Ag57(Dppp)4(C6H11S)32Cl2]Cl, with complete octameric fusion into [Au8Ag55(Dppp)4(C6H11S)34][BPh4]2, with incomplete octameric fusion. These observations will hopefully facilitate further research on the assembly of M13 nanobuilding blocks. 相似文献
994.
Jun‐Chao Liu Wei‐Qiang Liao Peng‐Fei Li Yuan‐Yuan Tang Xiao‐Gang Chen Xian‐Jiang Song Han‐Yue Zhang Yi Zhang Yu‐Meng You Ren‐Gen Xiong 《Angewandte Chemie (International ed. in English)》2020,59(9):3495-3499
Molecular ferroelectrics have attracted considerable interests because of their easy and environmentally friendly processing, low acoustical impedance and mechanical flexibility. Herein, a molecular thermochromic ferroelectric, N,N′‐dimethyl‐1,4‐diazoniabicyclo[2.2.2]octonium tetrachlorocuprate(II) ([DMe‐DABCO]CuCl4) is reported, which shows both excellent ferroelectricity and intriguing thermochromism. [DMe‐DABCO]CuCl4 undergoes a ferroelectric phase transition from Pca21 to Pbcm at a significantly high Curie temperature of 413 K, accompanied by a color change from yellow to red that is due to the remarkable deformation of [CuCl4]2? tetrahedron, where the ferroelectric and paraelectric phases correspond to yellow and red, respectively. Combined with multiple bistable physical properties, [DMe‐DABCO]CuCl4 would be a promising candidate for next‐generation smart devices, and should inspire further exploration of multifunctional molecular ferroelectrics. 相似文献
995.
Nan Zhang Leigang Li Juan Wang Zhiwei Hu Qi Shao Xiangheng Xiao Xiaoqing Huang 《Angewandte Chemie (International ed. in English)》2020,59(21):8066-8071
Surface regulation is an effective strategy to improve the performance of catalysts, but it has been rarely demonstrated for nitrogen reduction reaction (NRR) to date. Now, surface‐rough Rh2Sb nanorod (RNR) and surface‐smooth Rh2Sb NR (SNR) were selectively created, and their performance for NRR was investigated. The high‐index‐facet bounded Rh2Sb RNRs/C exhibit a high NH3 yield rate of 228.85±12.96 μg h?1 mg?1Rh at ?0.45 V versus reversible hydrogen electrode (RHE), outperforming the Rh2Sb SNRs/C (63.07±4.45 μg h?1 mg?1Rh) and Rh nanoparticles/C (22.82±1.49 μg h?1 mg?1Rh), owing to the enhanced adsorption and activation of N2 on high‐index facets. Rh2Sb RNRs/C also show durable stability with negligible activity decay after 10 h of successive electrolysis. The present work demonstrates that surface regulation plays an important role in promoting NRR activity and provides a new strategy for creating efficient NRR electrocatalysts. 相似文献
996.
Zhu Mao Yutong Ye Haiming Lv Xiao Xia Han Yeonju Park Libin Zang Bing Zhao Young Mee Jung 《Angewandte Chemie (International ed. in English)》2020,59(27):10780-10784
Interfaces play an important role in enhancing the energy conversion performance of dye‐sensitized solar cells (DSCs). The interface effects have been studied by many techniques, but most of the studies only focused on one part of a DSC, rather than on a complete solar cell. Hence, monitoring the interface evolution of a DSC is still very challenging. Here, in situ/operando resonance Raman (RR) spectroscopic analyses were carried out to monitor the dynamics of the photovoltaic conversion processes in a DSC. We observed the creation of new species (i.e., polyiodide and iodine aggregates) in the photosensitization process. We also obtained molecular‐scale dynamic evidence that the bands from the C=C and C=N bonds of 2,2′‐bipyridyl (bpy), the S=C=N bonds of the NCS ligand, and photochemical products undergo reasonably strong intensity and frequency changes, which clearly demonstrates that they are involved in charge separation. Furthermore, RR spectroscopy can also be used to quickly evaluate the performance of DSCs. 相似文献
997.
Fu‐Peng Wu Yang Yuan Claas Schünemann Paul C. J. Kamer Xiao‐Feng Wu 《Angewandte Chemie (International ed. in English)》2020,59(26):10451-10455
The borocarbonylative coupling of unactivated alkenes with alkyl halides remains a challenge. In this communication, a Cu‐catalyzed borocarbonylative coupling of unactivated alkenes with alkyl halides for the synthesis of β‐boryl ketones has been developed. A broad range of β‐boryl ketone derivatives was prepared in moderate to excellent yields with complete regioselectivity. 相似文献
998.
Li Ding Dan Xiao Zong Lu Junjie Deng Yanying Wei Jürgen Caro Haihui Wang 《Angewandte Chemie (International ed. in English)》2020,59(22):8720-8726
Membrane‐based reverse electrodialysis (RED) is considered as the most promising technique to harvest osmotic energy. However, the traditional membranes are limited by high internal resistance and low efficiency, resulting in undesirable power densities. Herein, we report the combination of oppositely charged Ti3C2Tx MXene membranes (MXMs) with confined 2D nanofluidic channels as high‐performance osmotic power generators. The negatively or positively charged 2D MXene nanochannels exhibit typical surface‐charge‐governed ion transport and show excellent cation or anion selectivity. By mixing the artificial sea water (0.5 m NaCl) and river water (0.01 m NaCl), we obtain a maximum power density of ca. 4.6 Wm?2, higher than most of the state‐of‐the‐art membrane‐based osmotic power generators, and very close to the commercialization benchmark (5 Wm?2). Through connecting ten tandem MXM‐RED stacks, the output voltage can reach up 1.66 V, which can directly power the electronic devices. 相似文献
999.
Fan Xiao Lin Lin Zhicong Chao Chen Shao Zhe Chen Zixiang Wei Jingxiong Lu Yishun Huang Lanqing Li Quan Liu Yongye Liang Leilei Tian 《Angewandte Chemie (International ed. in English)》2020,59(24):9702-9710
DNA nanotechnology plays an increasingly important role in the biomedical field; however, its application in the design of organic nanomaterials is underexplored. Herein, we report the use of DNA nanotechnology to transport a NIR‐II‐emitting nanofluorophore across the blood–brain barrier (BBB), facilitating non‐invasive imaging of brain tumors. Specifically, the DNA block copolymer, PS‐b‐DNA, is synthesized through a solid‐phase click reaction. We demonstrate that its self‐assembled structure shows exceptional cluster effects, among which BBB‐crossing is the most notable. Therefore, PS‐b‐DNA is utilized as an amphiphilic matrix to fabricate a NIR‐II nanofluorephore, which is applied in in vivo bioimaging. Accordingly, the NIR‐II fluorescence signal of the DNA‐based nanofluorophore localized at a glioblastoma is 3.8‐fold higher than the NIR‐II fluorescence signal of the PEG‐based counterpart. The notably increased imaging resolution will significantly benefit the further diagnosis and therapy of brain tumors. 相似文献
1000.