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991.
Dr. Greggory T. Kent Emily Morgan Kaitlin R. Albanese Dr. Anna Kallistova Dr. Alexandra Brumberg Linus Kautzsch Dr. Guang Wu Prof. Pratap Vishnoi Prof. Ram Seshadri Prof. Anthony K. Cheetham 《Angewandte Chemie (International ed. in English)》2023,62(32):e202306000
Halide double perovskites [A2MIMIIIX6] are an important class of materials that have garnered substantial interest as non-toxic alternatives to conventional lead iodide perovskites for optoelectronic applications. While numerous studies have examined chloride and bromide double perovskites, reports of iodide double perovskites are rare, and their definitive structural characterization has not been reported. Predictive models have aided us here in the synthesis and characterization of five iodide double perovskites of general formula Cs2NaLnI6 (Ln=Ce, Nd, Gd, Tb, Dy). The complete crystal structures, structural phase transitions, optical, photoluminescent, and magnetic properties of these compounds are reported. 相似文献
992.
Guodong Chen Jinran Sun Jiedong Li Dr. Xiaofan Du Gaojie Xu Prof. Shanmu Dong Prof. Guanglei Cui 《Angewandte Chemie (International ed. in English)》2023,62(31):e202306141
The Germanium (Ge), as a fast-charging and high specific capacity (1568 mAh g−1) alloy anode, is greatly hampered in practical application by poor cyclability. To date, the understanding of cycling performance degradation remains elusive. This study illustrates that, contrary to conventional beliefs, most of the Ge material in failed anodes still retains good integrity and does not undergo severe pulverization. It is revealed that capacity degradation is clearly correlated to the interfacial evolution of lithium hydride (LiH). Tetralithium germanium hydride (Li4Ge2H), as a new species derived from LiH, is identified as the culprit of Ge anode degradation, which is the dominant crystalized component in an ever-growing and ever-insulating interphase. The significantly increased thickness of the solid electrolyte interface (SEI) is accompanied by the accumulation of insulating Li4Ge2H upon cycling, which severely retards the charge transport process and ultimately triggers the anode failure. We believe that the comprehensive understanding of the failure mechanism presented in this study is of great significance to promoting the design and development of alloy anode for the next generation of lithium-ion batteries. 相似文献
993.
Dr. Meng Lu Shuai-Bing Zhang Ming-Yi Yang Yu-Fei Liu Jia-Peng Liao Pei Huang Dr. Mi Zhang Prof. Shun-Li Li Prof. Zhong-Min Su Prof. Ya-Qian Lan 《Angewandte Chemie (International ed. in English)》2023,62(31):e202307632
In this work, we innovatively assembled two types of traditional photosensitizers, that is pyridine ruthenium/ferrum (Ru(bpy)32+/Fe(bpy)32+) and porphyrin/metalloporphyrin complex (2HPor/ZnPor) by covalent linkage to get a series of dual photosensitizer-based three-dimensional metal-covalent organic frameworks (3D MCOFs), which behaved strong visible light-absorbing ability, efficient electron transfer and suitable band gap for highly efficient photocatalytic hydrogen (H2) evolution. Rubpy-ZnPor COF achieved the highest H2 yield (30 338 μmol g−1 h−1) with apparent quantum efficiency (AQE) of 9.68 %@420 nm, which showed one of the best performances among all reported COF based photocatalysts. Furthermore, the in situ produced H2 was successfully tandem used in the alkyne hydrogenation with ≈99.9 % conversion efficiency. Theoretical calculations reveal that both the two photosensitizer units in MCOFs can be photoexcited and thus contribute optimal photocatalytic activity. This work develops a general strategy and shows the great potential of using multiple photosensitive materials in the field of photocatalysis. 相似文献
994.
Xiang-Zhu Wei Tian-Yu Ding Dr. Yang Wang Dr. Bing Yang Dr. Qing-Qing Yang Prof. Dr. Shengfa Ye Prof. Dr. Chen-Ho Tung Prof. Dr. Li-Zhu Wu 《Angewandte Chemie (International ed. in English)》2023,62(36):e202308192
High-valent iron-oxo species are appealing for conducting O−O bond formation for water oxidation reactions. However, their high reactivity poses a great challenge to the dissection of their chemical transformations. Herein, we introduce an electron-rich and oxidation-resistant ligand, 2-[(2,2′-bipyridin)-6-yl]propan-2-ol to stabilize such fleeting intermediates. Advanced spectroscopies and electrochemical studies demonstrate a high-valent FeV(O) species formation in water. Combining kinetic and oxygen isotope labelling experiments and organic reactions indicates that the FeV(O) species is responsible for O−O bond formation via water nucleophilic attack under the real catalytic water oxidation conditions. 相似文献
995.
Xiaofang Bai Xiuping Zhang Yujiao Sun Mingcheng Huang Prof. Dr. Jiantao Fan Prof. Dr. Shaoyi Xu Prof. Dr. Hui Li 《Angewandte Chemie (International ed. in English)》2023,62(38):e202308704
To date, only a few noble metal oxides exhibit the required efficiency and stability as oxygen evolution reaction (OER) catalysts under the acidic, high-voltage conditions that exist during proton exchange membrane water electrolysis (PEMWE). The high cost and scarcity of these catalysts hinder the large-scale application of PEMWE. Here, we report a novel OER electrocatalyst for OER comprised of uniformly dispersed Ru clusters confined on boron carbon nitride (BCN) support. Compared to RuO2, our BCN-supported catalyst shows enhanced charge transfer. It displays a low overpotential of 164 mV at a current density of 10 mA cm−2, suggesting its excellent OER catalytic activity. This catalyst was able to operate continuously for over 12 h under acidic conditions, whereas RuO2 without any support fails in 1 h. Density functional theory (DFT) calculations confirm that the interaction between the N on BCN support and Ru clusters changes the adsorption capacity and reduces the OER energy barrier, which increases the electrocatalytic activity of Ru. 相似文献
996.
Zejing Xing Xiaodan Gou Prof. Dr. Li-Ping Jiang Prof. Dr. Jun-Jie Zhu Dr. Cheng Ma 《Angewandte Chemie (International ed. in English)》2023,62(39):e202308950
Protein coronas are present extensively at the bio-nano interface due to the natural adsorption of proteins onto nanomaterials in biological fluids. Aside from the robust property of nanoparticles, the dynamics of the protein corona shell largely define their chemical identity by altering interface properties. However, the soft coronas are normally complex and rapidly changing. To real-time monitor the entire formation, we report here a self-regulated electrochemiluminescence (ECL) microscopy based on the interaction of the Ru(bpy)33+ with the nanoparticle surface. Thus, the heterogeneity of the protein corona is in situ observed in single nanoparticle “cores” before and after loading drugs in nanomedicine carriers. The label-free, optical stable and dynamic ECL microscopy minimize misinterpretations caused by the variation of nanoparticle size and polydispersity. Accordingly, the synergetic actions of proteins and nanoparticles properties are uncovered by chemically engineered protein corona. After comparing the protein corona formation kinetics in different complex systems and different nanomedicine carriers, the universality and accuracy of this technique were well demonstrated via the protein corona formation kinetics curves regulated by competitive adsorption of Ru(bpy)33+ and multiple proteins on surface of various carriers. The work is of great significance for studying bio-nano interface in drug delivery and targeted cancer treatment. 相似文献
997.
Dr. Hongshuang Guo Dr. Chen Liang Dr. Tero-Petri Ruoko Dr. Henning Meteling Dr. Bo Peng Dr. Hao Zeng Prof. Arri Priimagi 《Angewandte Chemie (International ed. in English)》2023,62(43):e202309402
Shape-changing polymeric materials have gained significant attention in the field of bioinspired soft robotics. However, challenges remain in versatilizing the shape-morphing process to suit different tasks and environments, and in designing systems that combine reversible actuation and self-healing ability. Here, we report halogen-bonded liquid crystal elastomers (LCEs) that can be arbitrarily shape-programmed and that self-heal under mild thermal or photothermal stimulation. We incorporate halogen-bond-donating diiodotetrafluorobenzene molecules as dynamic supramolecular crosslinks into the LCEs and show that these relatively weak crosslinks are pertinent for their mechanical programming and self-healing. Utilizing the halogen-bonded LCEs, we demonstrate proof-of-concept soft robotic motions such as crawling and rolling with programmed velocities. Our results showcase halogen bonding as a promising, yet unexplored tool for the preparation of smart supramolecular constructs for the development of advanced soft actuators. 相似文献
998.
Dr. Yunxiang Li Dr. Yan Guo Dr. Deyan Luan Prof. Xiaojun Gu Prof. Xiong Wen Lou 《Angewandte Chemie (International ed. in English)》2023,62(44):e202310847
Developing highly efficient catalytic sites for O2 reduction to H2O2, while ensuring the fast injection of energetic electrons into these sites, is crucial for artificial H2O2 photosynthesis but remains challenging. Herein, we report a strongly coupled hybrid photocatalyst comprising polymeric carbon nitride (CN) and a two-dimensional conductive Zn-containing metal–organic framework (Zn-MOF) (denoted as CN/Zn-MOF(lc)/400; lc, low crystallinity; 400, annealing temperature in °C), in which the catalytic capability of Zn-MOF(lc) for H2O2 production is unlocked by the annealing-induced effects. As revealed by experimental and theoretical calculation results, the Zn sites coordinated to four O (Zn-O4) in Zn-MOF(lc) are thermally activated to a relatively electron-rich state due to the annealing-induced local structure shrinkage, which favors the formation of a key *OOH intermediate of 2e− O2 reduction on these sites. Moreover, the annealing treatment facilitates the photoelectron migration from the CN photocatalyst to the Zn-MOF(lc) catalytic unit. As a result, the optimized catalyst exhibits dramatically enhanced H2O2 production activity and excellent stability under visible light irradiation. 相似文献
999.
Hyehwang Kim Dr. Zheng-wang Qu Prof. Dr. Stefan Grimme Nahil Al-Zuhaika Prof. Dr. Douglas W. Stephan 《Angewandte Chemie (International ed. in English)》2023,62(43):e202312587
The phosphino-phosphonium cations of the form [R3PPR′2]+ are labile and provide access to the constituent Lewis acidic and Lewis basic fragments. This permits frustrated Lewis pair-type addition reactions to alkynes, affording unprecedented phosphino-phosphination reactions and giving cations of the form [cis-R3PCHC(R′′)PR′2]+. This reactivity is further adapted to prepare several examples of a rare class of dissymmetric cis-olefin-linked bidentate phosphines. 相似文献
1000.
Philip M. Keil Ademola Soyemi Kilian Weisser Prof. Tibor Szilvási Prof. Christian Limberg Dr. Terrance J. Hadlington 《Angewandte Chemie (International ed. in English)》2023,62(19):e202381961
The open-shell cationic stannylene-iron(0) complex 4 ( 4 =[PhiPDippSn⋅Fe⋅IPr]+; PhiPDipp={[Ph2PCH2Si(iPr)2](Dipp)N}; Dipp=2,6-iPr2C6H3; IPr=[(Dipp)NC(H)]2C:) cooperatively and reversibly cleaves dihydrogen at the Sn−Fe interface under mild conditions (1.5 bar, 298 K), in forming bridging hydrido-complex 6 . The One-electron oreduction of the related GeII−Fe0 complex 3 leads to oxidative addition of one C−P linkage of the PhiPDipp ligand in an intermediary Fe−I complex, leading to FeI phosphide species 7 . One-electron reduction reaction of 4 gives access to the iron(−I) ferrato-stannylene, 8 , giving evidence for the transient formation of such a species in the reduction of 3 . The covalently bound tin(II)-iron(−I) compound 8 has been characterised through EPR spectroscopy, SQUID magnetometry, and supporting computational analysis, which strongly indicate a high localization of electron spin density at Fe−I in this unique d9-iron complex. 相似文献