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41.
Chunlin Xie Shengfang Liu Zefang Yang Huimin Ji Shuhan Zhou Hao Wu Chao Hu Yougen Tang Xiaobo Ji Qi Zhang Haiyan Wang 《Angewandte Chemie (International ed. in English)》2023,62(16):e202218612
Developing a highly stable and dendrite-free zinc anode is essential to the commercial application of zinc metal batteries. However, the understanding of zinc dendrites formation mechanism is still insufficient. Herein, for the first time, we discover that the interfacial heterogeneous deposition induced by lattice defects and epitaxial growth limited by residual stress are intrinsic and critical causes for zinc dendrite formation. Therefore, an annealing reconstruction strategy was proposed to eliminate lattice defects and stresses in zinc crystals, which achieve dense epitaxial electrodeposition of zinc anode. The as-prepared annealed zinc anodes exhibit dendrite-free morphology and enhanced electrochemical cycling stability. This work first proves that lattice defects and residual stresses are also very important factors for epitaxial electrodeposition of zinc in addition to crystal orientation, which can provide a new mechanism for future researches on zinc anode modification. 相似文献
42.
Caitlin E. Shields Dr. Xue Wang Dr. Thomas Fellowes Rob Clowes Dr. Linjiang Chen Prof. Graeme M. Day Prof. Anna G. Slater Dr. John W. Ward Dr. Marc A. Little Prof. Andrew I. Cooper 《Angewandte Chemie (International ed. in English)》2023,62(34):e202303167
Hydrogen-bonded organic frameworks (HOFs) with low densities and high porosities are rare and challenging to design because most molecules have a strong energetic preference for close packing. Crystal structure prediction (CSP) can rank the crystal packings available to an organic molecule based on their relative lattice energies. This has become a powerful tool for the a priori design of porous molecular crystals. Previously, we combined CSP with structure-property predictions to generate energy-structure-function (ESF) maps for a series of triptycene-based molecules with quinoxaline groups. From these ESF maps, triptycene trisquinoxalinedione (TH5) was predicted to form a previously unknown low-energy HOF (TH5-A) with a remarkably low density of 0.374 g cm−3 and three-dimensional (3D) pores. Here, we demonstrate the reliability of those ESF maps by discovering this TH5-A polymorph experimentally. This material has a high accessible surface area of 3,284 m2 g−1, as measured by nitrogen adsorption, making it one of the most porous HOFs reported to date. 相似文献
43.
Martin Möbs Prof. David A. Dixon Dr. Gabriel F. de Melo Dr. Monica Vasiliu Tim Graubner Prof. Karl O. Christe Prof. Florian Kraus 《Angewandte Chemie (International ed. in English)》2023,62(39):e202307218
The purely chemical synthesis of fluorine is a spectacular reaction which for more than a century had been believed to be impossible. In 1986, it was finally experimentally achieved, but since then this important reaction has not been further studied and its detailed mechanism had been a mystery. The known thermal stability of MnF4 casts serious doubts on the originally proposed hypothesis that MnF4 is thermodynamically unstable and decomposes spontaneously to a lower manganese fluoride and F2. This apparent discrepancy has now been resolved experimentally and by electronic structure calculations. It is shown that the reductive elimination of F2 requires a large excess of SbF5 and occurs in the last reaction step when in the intermediate [SbF6][MnF2][Sb2F11] the addition of one more SbF5 molecule to the [SbF6]− anion generates a second tridentate [Sb2F11]− anion. The two tridentate [Sb2F11]− anions then provide six fluorine bridges to the Mn atom thereby facilitating the reductive elimination of the two fluorine ligands as F2. 相似文献
44.
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
45.
Kaofeng Huang Haiyi Qiu Xintong Zhang Wang Luo Ying Chen Jiacheng Zhang Prof. Yihang Chen Prof. Guannan Wang Prof. Kezhi Zheng 《Angewandte Chemie (International ed. in English)》2023,62(14):e202218491
Materials with tunable emission colors has attracted increasing interest in both fundamental research and applications. As a key member of light-emitting materials family, lanthanide doped upconversion nanoparticles (UCNPs) have been intensively demonstrated to emit light in any color upon near-infrared excitation. However, realizing the trichromatic emission in UCNPs with a fixed composition remains a great challenge. Here, without excitation pulsed modulation and three different near-infrared pumping, we report an experimental design to fine-control emission in the full color gamut from core–shell-structured UCNPs by manipulating the energy migration through dual-channel pump scheme. We also demonstrate their potential application in full-color display. These findings may benefit the future development of convenient and versatile optical methos for multicolor tuning and open up the possibility of constructing full-color volumetric display systems with high spatiotemporal resolution. 相似文献
46.
Basem Moosa Lukman O. Alimi Weibin Lin Aliyah Fakim Prashant M. Bhatt Mohamed Eddaoudi Niveen M. Khashab 《Angewandte Chemie (International ed. in English)》2023,62(46):e202311555
Porous molecular sorbents have excellent selectivity towards hydrocarbon separation with energy saving techniques. However, to realize commercialization, molecular sieving processes should be faster and more efficient compared to extended frameworks. In this work, we show that utilizing fluorine to improve the hydrophobic profile of leaning pillararenes affords a substantial kinetic selective adsorption of benzene over cyclohexane (20 : 1 for benzene). The crystal structure shows a porous macrocycle that acts as a perfect match for benzene in both the intrinsic and extrinsic cavities with strong interactions in the solid state. The fluorinated leaning pillararene surpasses all reported organic molecular sieves and is comparable to the extended metal–organic frameworks that were previously employed for this separation such as UIO-66. Most importantly, this sieving system outperformed the well-known zeolitic imidazolate frameworks under low pressure, which opens the door to new generations of molecular sieves that can compete with extended frameworks for more sustainable hydrocarbon separation. 相似文献
47.
Peng Zhu Jinshan Wang Fei Xia Wei Zhang Haiou Liu Prof. Xiongfu Zhang 《欧洲无机化学杂志》2023,26(9):e202200664
Sheet-like ZSM-5 has been regarded as a promising material for catalytic applications due to its diffusion superiority. However, it still remains a challenge to obtain a desirable sheet-like morphology because of the complex synthesis process of zeolites. Here, a facile strategy for synthesizing sheet-like ZSM-5 is developed by only adding ethanol as zeolite growth modifier in the synthesis gel. It is thought that ethanol might be preferentially absorbed on the {010} surface of zeolite crystals, interact with the exposed silicon hydroxyl groups on the crystal {010} facet, and suppress the growth of b axis, resulting in the sheet-like shape. Through finely tunning synthesis parameters, sheet-like ZSM-5 crystals with thin b-axis thickness of 90 nm and different aspect ratios could be obtained. Owing to its shorter diffusion path and optimized acidity, sheet-like ZSM-5 exhibits better catalytic performance than conventional ZSM-5 in the alkylation of benzene with ethanol. 相似文献
48.
Florian Pachel Dr. Markus Ströbele Carl P. Romao David Enseling Thomas Jüstel Prof. Dr. Hans-Jürgen Meyer 《欧洲无机化学杂志》2023,26(19):e202300096
The new heteroleptic tungsten iodide cluster compound [W6I12(NCC6H5)2] is presented. The synthesis is carried-out from Cs2W6I14 and ZnI2 under solvothermal conditions in benzonitrile solution, yielding red cube-shaped crystals. [W6I12(NCC6H5)2] represents a heteroleptic [W6I8]-type cluster bearing four apical iodides and two benzonitrile ligands. Molecular [W6I12(NCC6H5)2] clusters form a robust hydrogen bridged crystal structure with high thermal stability and high resistibility against hydrolysis. The electronic structure is analyzed by quantum chemical methods of the calculated electron localization function (ELF) and the band structure. Photoluminescence measurements are performed to verify and describe the photophysical properties of [W6I12(NCC6H5)2]. Finally, the photocatalytic properties of [W6I12(NCC6H5)2] are evaluated as a proof-of-concept. 相似文献
49.
Dr. Aline Varella Rodrigues Bruno Seiki Domingos Onishi Prof. Dr. Sidney José Lima Ribeiro 《Chemphyschem》2023,24(21):e202300134
This research endeavors to overcome the significant challenge of developing materials that simultaneously possess photostability and photosensitivity to UV-visible irradiation. Sulfurized nanorod (NR)-like ZnO/Zn(OH)2 and hierarchical flower-like γ-Zn(OH)2/ϵ-Zn(OH)2 were identified from XRD diffraction patterns and Raman vibrational modes. The sulfurized material, observed by FEG-SEM and TEM, showed diameters ranging from 10 and 40 nm and lengths exceeding 200 nm. The S2− ions intercalated Zn2+, modulating NRs to dumbbell-like microrods. SAED and HRTEM illustrated the atomic structure in (101) crystal plane. Its direct band gap of 3.0 eV was attributed to the oxygen vacancies, which also contribute to the deep-level emissions at 422 and 485 nm. BET indicated specific surface area of 4.4 m2 g−1 and pore size as mesoporosity, which are higher compared to the non-sulfurized analogue. These findings were consistent with the observed photocurrent, photostability and photoluminescence (PL), further supporting the suitability of sulfurized NR-like ZnO/Zn(OH)2 as a promising candidate for Luminescent solar concentrators (LSC)-photovoltaic (PV) system. 相似文献
50.
《印度化学会志》2023,100(9):101074
In this paper, we report a facile and one-pot hydrothermal synthesis of FeVO4-rGO nanorod composite and its application as a heterogeneous catalyst in the oxidative esterification reaction of aldehydes using hydrogen peroxide oxidant. The nanomaterial is thoroughly characterized by different techniques, namely, XPS, FESEM, elemental mapping, XRD, Raman, HRTEM, etc. The as-prepared nanocatalyst shows good activity for the controlled base-free oxidative esterification of various aromatic aldehydes in alcohol solvents under refluxing conditions, achieving good yields of the desired esters. Furthermore, the substrate scope was explored over a wide array of substituted aromatic aldehydes with diverse electron-withdrawing and electron-donating groups in the phenyl ring. The presence of heterogeneous interfaces-induced properties in the nanorod composite results in synergistic effects to provide good catalytic performance. Thus, binary transition metal oxide-reduced graphene oxide-based nanocomposite as a nanocatalyst can open doors for efficient and sustainable esterification of aromatic aldehydes and aliphatic alcohols under oxidative conditions. 相似文献