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101.
Unprecedented Oxidative Addition and Metal‐Only Lewis Pair Chemistry of Antimony Trihalides
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Prof. Dr. Holger Braunschweig Dr. Rian D. Dewhurst Florian Hupp Dr. Justin Wolf 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(5):1860-1862
Reaction of the zero‐valent platinum complex [Pt(PCy3)2] with SbF3 generates the cationic diplatinum stibenium complex [{(Cy3P)2Pt}2(μ‐SbF2)]+, the first unsupported metal‐only Lewis pair containing an antimony‐centered Lewis acid. In contrast, SbCl3 undergoes oxidative addition to [Pt(PCy3)2], resulting in the dihalostibanyl complex trans‐[PtCl(SbCl2)(PCy3)2], the first example of oxidative addition of an antimony–halide bond to a transition metal. 相似文献
102.
Dr. Fabian O. von Rohr Alice Ryser Dr. Huiwen Ji Dr. Karoline Stolze Dr. Jing Tao Jessica J. Frick Prof. Greta R. Patzke Prof. Robert J. Cava 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(8):2082-2088
We describe the previously unreported oxygen excess hexagonal antimony tungsten bronze with composition Sb0.5W3O10, in the following denoted as h-SbxWO3+2x with x=0.167, to demonstrate its analogy to classical AxWO3 tungsten bronzes. This compound forms in a relatively narrow temperature range between 580 °C<T<620 °C. It was obtained as a dark-blue polycrystalline powder, and as thin, needle-shaped, blue single crystals. h-SbxWO3+2x crystallizes in the hexagonal space group P6/mmm with the cell parameters a=7.4369(4) Å and c=3.7800(2) Å. The antimony and excess oxygen occupy the hexagonal channels within the network of corner-sharing WO6 octahedra. h-SbxWO3+2x has a resistivity of ρ300 K≈1.28 mΩ cm at room temperature, with little if any temperature-dependence on cooling. DFT calculations on a simplified model for this compound find a metallic-like electronic structure with the Fermi level falling within rather flat bands, especially around the Γ point. 相似文献
103.
104.
Caroline K. Williams Gavin A. McCarver Ashwin Chaturvedi Dr. Soumalya Sinha Marcus Ang Prof. Konstantinos D. Vogiatzis Prof. Jianbing “Jimmy” Jiang 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(52):e202201323
Electrocatalytic hydrogen gas production is considered a potential pathway towards carbon-neutral energy sources. However, the development of this technology is hindered by the lack of efficient, cost-effective, and environmentally benign catalysts. In this study, a main-group-element-based electrocatalyst, SbSalen , is reported to catalyze the hydrogen evolution reaction (HER) in an aqueous medium. The heterogenized molecular system achieved a Faradaic efficiency of 100 % at −1.4 V vs. NHE with a maximum current density of −30.7 mA/cm2. X-ray photoelectron spectroscopy of the catalyst-bound working electrode before and after electrolysis confirmed the molecular stability during catalysis. The turnover frequency was calculated as 43.4 s−1 using redox-peak integration. The kinetic and mechanistic aspects of the electrocatalytic reaction were further examined by computational methods. This study provides mechanistic insights into main-group-element electrocatalysts for heterogeneous small-molecule conversion. 相似文献
105.
WO3 nanofiber bundles with high photocatalytic activity have been synthesized through the soluble salt-assisted hydrothermal method. 相似文献
106.
Dr. Xianfu Wang Yiming Xie Kai Tang Chao Wang Prof. Chenglin Yan 《Angewandte Chemie (International ed. in English)》2018,57(36):11569-11573
Hydrogen ions are ideal charge carriers for rechargeable batteries due to their small ionic radius and wide availability. However, little attention has been paid to hydrogen‐ion storage devices because they generally deliver relatively low Coulombic efficiency as a result of the hydrogen evolution reaction that occurs in an aqueous electrolyte. Herein, we successfully demonstrate that hydrogen ions can be electrochemically stored in an inorganic molybdenum trioxide (MoO3) electrode with high Coulombic efficiency and stability. The as‐obtained electrode exhibits ultrafast hydrogen‐ion storage properties with a specific capacity of 88 mA hg?1 at an ultrahigh rate of 100 C. The redox reaction mechanism of the MoO3 electrode in the hydrogen‐ion cell was investigated in detail. The results reveal a conversion reaction of the MoO3 electrode into H0.88MoO3 during the first hydrogen‐ion insertion process and reversible intercalation/deintercalation of hydrogen ions between H0.88MoO3 and H0.12MoO3 during the following cycles. This study reveals new opportunities for the development of high‐power energy storage devices with lightweight elements. 相似文献
107.
Vanessa A. Béland Zhiqiang Wang Prof. Tsun‐Kong Sham Prof. Paul J. Ragogna 《Angewandte Chemie (International ed. in English)》2018,57(40):13252-13256
The synthesis of phosphane‐ene photopolymer networks, where the networks are composed of crosslinked tertiary alkyl phosphines are reported. Taking advantage of the rich coordination chemistry of alkyl phosphines, stibino‐phosphonium and stibino‐bis(phosphonium) functionalized polymer networks could be generated. Small‐molecule stibino‐phosphonium and stibino‐bis(phosphonium) compounds have been well characterized previously and were used as models for spectroscopic comparison to the macromolecular analogues by NMR and XANES spectroscopy. This work reveals that the physical and electronic properties of the materials can be tuned depending on the type of coordination environment. These materials can be used as ceramic precursors, where the Sb‐functionalized polymers influence the composition of the resulting ceramic. 相似文献
108.
Dr. Xin Wang Dr. Junjie He Dr. Benqing Zhou Dr. Youming Zhang Dr. Jiatao Wu Dr. Rui Hu Prof. Liwei Liu Prof. Jun Song Prof. Junle Qu 《Angewandte Chemie (International ed. in English)》2018,57(28):8668-8673
As a highly stable band gap semiconductor, antimonene is an intriguing two‐dimensional (2D) material in optoelectronics. However, its short layer distance and strong binding energy make it challenging to prepare high‐quality large 2D antimonene; therefore, its predicted tunable band gap has not been experimentally confirmed. Now, an approach to prepare smooth and large 2D antimonene with uniform layers that uses a pregrinding and subsequent sonication‐assisted liquid‐phase exfoliation process has been established. Mortar pregrinding provides a shear force along the layer surfaces, forming large, thin antimony plates, which can then easily be exfoliated into smooth, large antimonene, avoiding long sonication times and antimonene destruction. The resulting antimonene also enabled verification of the tunable band gap from 0.8 eV to 1.44 eV. Hole extraction and current enhancement by about 30 % occurred when the antimonene was used as a hole transport layer in perovskite solar cells. 相似文献
109.
Janusz Lipkowski Marina S. Fonari Victor Ch. Kravtsov Yurii A. Simonov Edward V. Ganin Vladimir O. Gelmboldt 《Journal of chemical crystallography》1996,26(12):823-833
Four crystalline molecular complexes between antimony(III) fluoride and 18-membered crown ethers have been obtained and their structures investigated by single crystal X-ray diffraction techniques: [18-crown-6·SbF3], C12H24F3O6Sb,P212121,a=8.328(4),b=11.573(4),c=18.094(4),V=1744(1)3,Z=4; [benzo-18-crown-6·SbF3], C16H24F3O6Sb,P21/n,a=10.490(2),b=13.714(1),c=13.442(2), =101.94(1)°,V=1892(1)3,Z=4; [cis-syn-cis-dicyclohexano-18-crown-6·SbF3·CH3OH], C21H40F3O7Sb,P21/n,a=8.270(4),b=23.386(3),c=12.772(1), =96.31(2)°,V=2455(1)3,Z=4; [cis-anti-cis-dicyclohexano-18-crown-6·SbF3], C20H36F3O6Sb,Pna21,a=21.091(8),b=12.829(5),c=8.437(3),V=2283(2)3,Z=4. All species are the perching-type complexes with the antimony fluoride above the cavity and the metal lone pair pointed toward the center of the crown ring. The antimony atom interacts with all six crown oxygen atoms with Sb–O distances of 2.837(2)–3.344(2) . The antimony atom is displaced from the least square plane of the crown oxygen atoms at the distances of 1.288–1.383 . 相似文献
110.
Thermal behaviour of the glass series (100-x)[50ZnO-10B2O3-40P2O5]·xSb2O3 (x=0-42 mol%) and (100-y)[60ZnO-10B2O3-30P2O5]·ySb2O3 (y=0-28 mol%) was investigated by DSC and TMA. The addition of Sb2O3 results in a decrease of the glass transition temperature and crystallization temperature in both compositional series. All
glasses crystallize on heating in the temperature range of 522–632°C. Thermal expansion coefficient of the glasses monotonously
increases with increasing Sb2O3 content in both series and varies within the range of 6.6–11.7 ppm °C−1. From changes of thermal capacity within the glass transition region it was concluded that with increasing Sb2O3 content the ‘fragility’ of the studied glasses increases. 相似文献