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1.
Ruyi Bi Dr. Nan Xu Hao Ren Prof. Nailiang Yang Dr. Yonggang Sun Prof. Anmin Cao Prof. Ranbo Yu Prof. Dan Wang 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(12):4895-4898
The lithium-ion capacitor (LIC) has attracted tremendous research interest because it meets both the requirement on high energy and power densities. The balance between effective surface areas and mass transport is highly desired to fabricate the optimized electrode material for LIC. Now, triple-shelled (3S) Nb2O5 hollow multi-shelled structures (HoMSs) were synthesized for the first time through the sequential templating approach and then applied for the anode of LIC. The unique structure of HoMSs, such as large efficient surface area, hierarchical pores, and multiple shells, provides abundant reaction sites, decreases the electron transport resistance, and increases the diffusion rate for ion transport. In this case, the best combination performance has been achieved among all the reported Nb2O5-based materials, which delivered an excellent energy and power densities simultaneously, and superb cycling stability. 相似文献
2.
Jian Zhang Jiawei Wan Jiangyan Wang Hao Ren Ranbo Yu Lin Gu Yunling Liu Shouhua Feng Dan Wang 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(16):5320-5325
Herein, we present heterogeneous hollow multi‐shelled structures (HoMSs) prepared by exploiting the properties of the metal–organic framework (MOFs) casing. Through accurately controlling the transformation of MOF layer into different heterogeneous casings, we can precisely design HoMSs of SnO2@Fe2O3(MOF) and SnO2@FeOx‐C(MOF), which not only retain properties of the original SnO2‐HoMSs, but also structural information from the MOFs. Tested as anode materials in LIBs, SnO2@Fe2O3 (MOF)‐HoMSs demonstrate superior lithium‐storage capacity and cycling stability to the original SnO2‐HoMSs, which can be attributed to the topological features from the MOF casing. Making a sharp contrast to the electrodes of SnO2@Fe2O3 (particle)‐HoMSs fabricated by hydrothermal method, the capacity retention after 100 cycles for the SnO2@Fe2O3 (MOF)‐HoMSs is about eight times higher than that of the SnO2@Fe2O3 (particle)‐HoMS. 相似文献
3.
Yanze Wei Jiangyan Wang Ranbo Yu Jiawei Wan Dan Wang 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(5):1436-1440
Constructing hollow multi‐shelled structures (HoMSs) has a significant effect on promoting light absorption property of catalysts and enhancing their performance in solar energy conversion applications. A facile hydrothermal method is used to design the SrTiO3?TiO2 heterogeneous HoMSs by hydrothermal crystallization of SrTiO3 on the surface of the TiO2 HoMSs, which will realize a full coverage of SrTiO3 on the TiO2 surface and construct the SrTiO3/TiO2 junctions. The broccoli‐like SrTiO3?TiO2 heterogeneous HoMSs exhibited a fourfold higher overall water splitting performance of 10.6 μmol h?1 for H2 production and 5.1 μmol h?1 for O2 evolution than that of SrTiO3 nanoparticles and the apparent quantum efficiency (AQE) of 8.6 % at 365 nm, which can be mainly attributed to 1) HoMS increased the light absorption ability of the constructed photocatalysts and 2) the SrTiO3?TiO2 junctions boosted the separation efficiency of the photogenerated charge carriers. 相似文献
4.
Feifei You Jiawei Wan Jian Qi Dan Mao Nailiang Yang Qinghua Zhang Lin Gu Dan Wang 《Angewandte Chemie (International ed. in English)》2020,59(2):721-724
Precise control of the micro‐/nanostructures of nanomaterials, such as hollow multi‐shelled structures (HoMSs), has shown its great advantages in various applications. Now, the crystal structure of building blocks of HoMSs are controlled by introducing the lattice distortion in HoMSs, for the first time. The lattice distortion located at the nanoscale interface of SnS2/SnO2 can provide additional active sites, which not only provide the catalytic activity under visible light but also improve the separation of photoexcited electron–hole pairs. Combined with the efficient light utilization, the natural advantage of HoMSs, a record catalytic activity was achieved in solid–gas system for CO2 reduction, with an excellent stability and 100 % CO selectivity without using any sensitizers or noble metals. 相似文献
5.
Esmail Husein M. Salhabi Jilu Zhao Jiangyan Wang Mei Yang Bao Wang Dan Wang 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(27):9176-9180
TiO2?x with well‐controlled hollow multi‐shelled structures (HoMSs) were designed and synthesized, via a sequential templating approach (STA), to act as sulfur carrier materials. They were explored as physico‐chemical encapsulation materials. Particularly, the sulfur cathode based on triple‐shelled TiO2?x HoMSs delivered a specific capacity of 903 mAh g?1 with a capacity retention of 79 % at 0.5 C and a Coulombic efficiency of 97.5 % over 1000 cycles. The outstanding electrochemical performance is attributed to better spatial confinement and integrated conductivity of the intact triple‐shell that combine the features of physico‐chemical adsorption, short charge transfer path along with mechanical strength. 相似文献
6.
In this study, we explored the feasibility of using electrochemically generated γ‐LixV2O5 as an insertion‐type anode in the lithium‐ion capacitor (LIC) with activated carbon (AC) as a cathode. Along with the native form of V2O5, their carbon composites are also used as the electrode material which is prepared by high‐energy ball milling. The electrochemical pre‐lithiation strategy is used to generate the desired γ‐phase of V2O5 (γ‐LixV2O5). Under the optimized mass loading conditions, the LICs are assembled with γ‐LixV2O5 as anode and AC as a cathode in the organic medium. Among the different LICs fabricated, AC/γ‐LixV2O5‐BM50 configuration delivered an energy density of 33.91 Wh kg?1 @ 0.22 kW kg?1 with excellent capacity retention characteristics. However, a dramatic increase in energy density (43.98 Wh kg?1@0.28 kW kg?1) is noted after the electrolyte modification with fluoroethylene carbonate. The high temperature performance of the assembled LIC is also studied and found that γ‐LixV2O5 phase can be used as a potential battery‐type component to construct high‐performance hybrid charge storage devices. 相似文献
7.
Tomoyuki Kitano Dr. Tetsuya Shishido Dr. Kentaro Teramura Prof. Dr. Tsunehiro Tanaka 《Chemphyschem》2013,14(11):2560-2569
Thermally stable Brønsted acid sites were generated on alumina‐supported niobium oxide (Nb2O5/Al2O3) by calcination at high temperatures, such as 1123 K. The results of structural characterization by using Fourier‐transform infrared (FTIR) spectroscopy, TEM, scanning transmission electron microscopy (STEM), and energy‐dispersive X‐ray (EDX) analysis indicated that the Nb2O5 monolayer domains were highly dispersed over alumina at low Nb2O5 loadings, such as 5 wt %, and no Brønsted acid sites were presents. The coverage of Nb2O5 monolayer domains over Al2O3 increased with increasing Nb2O5 loading and almost‐full coverage was obtained at a loading of 16 wt %. A sharp increase in the number of hydroxy groups, which acted as Brønsted acid sites, was observed at this loading level. The relationship between the acidic properties and the structure of the material suggested that the bridging hydroxy groups (Nb? O(H)? Nb), which were formed at the boundaries between the domains of the Nb2O5 monolayer, acted as thermally stable Brønsted acid sites. 相似文献
8.
Julian Szczesny James A. Birrell Felipe Conzuelo Wolfgang Lubitz Adrian Ruff Wolfgang Schuhmann 《Angewandte Chemie (International ed. in English)》2020,59(38):16506-16510
The incorporation of highly active but also highly sensitive catalysts (e.g. the [FeFe] hydrogenase from Desulfovibrio desulfuricans) in biofuel cells is still one of the major challenges in sustainable energy conversion. We report the fabrication of a dual‐gas diffusion electrode H2/O2 biofuel cell equipped with a [FeFe] hydrogenase/redox polymer‐based high‐current‐density H2‐oxidation bioanode. The bioanodes show benchmark current densities of around 14 mA cm?2 and the corresponding fuel cell tests exhibit a benchmark for a hydrogenase/redox polymer‐based biofuel cell with outstanding power densities of 5.4 mW cm?2 at 0.7 V cell voltage. Furthermore, the highly sensitive [FeFe] hydrogenase is protected against oxygen damage by the redox polymer and can function under 5 % O2. 相似文献
9.
Advanced High‐Voltage Aqueous Lithium‐Ion Battery Enabled by “Water‐in‐Bisalt” Electrolyte 下载免费PDF全文
Dr. Liumin Suo Dr. Oleg Borodin Wei Sun Dr. Xiulin Fan Dr. Chongyin Yang Dr. Fei Wang Tao Gao Dr. Zhaohui Ma Dr. Marshall Schroeder Dr. Arthur von Cresce Dr. Selena M. Russell Prof. Michel Armand Prof. Austen Angell Dr. Kang Xu Prof. Chunsheng Wang 《Angewandte Chemie (International ed. in English)》2016,55(25):7136-7141
A new super‐concentrated aqueous electrolyte is proposed by introducing a second lithium salt. The resultant ultra‐high concentration of 28 m led to more effective formation of a protective interphase on the anode along with further suppression of water activities at both anode and cathode surfaces. The improved electrochemical stability allows the use of TiO2 as the anode material, and a 2.5 V aqueous Li‐ion cell based on LiMn2O4 and carbon‐coated TiO2 delivered the unprecedented energy density of 100 Wh kg?1 for rechargeable aqueous Li‐ion cells, along with excellent cycling stability and high coulombic efficiency. It has been demonstrated that the introduction of a second salts into the “water‐in‐salt” electrolyte further pushed the energy densities of aqueous Li‐ion cells closer to those of the state‐of‐the‐art Li‐ion batteries. 相似文献
10.
An instrument for a sputtered neutral mass spectrometry with a quadrupole mass spectrometer (QMS) by resonance‐enhanced multiphton ionization method is developed to study sputtered neutrals emission phenomena under ion irradiation in a low‐energy region. We have prepared a pulsed primary ion beam and an ion counting system, and have optimized the operation parameter including a sample bias, energy analyzer voltages, pulsed timing of laser and ion beam, etc. A yield ratio of the lowest‐lying excited state a5S2 to the ground state a7S3 for sputtered Cr atoms has been measured as a function of incident energy of Ar+ and O2+ down to 600 eV using a polycrystalline Cr sample. The yield ratio has become a constant value for the Ar+ incidence, while it has exponentially increased below 1 keV for the O2+ incidence. It is found that the internal energy distribution of sputtered Cr atoms has been significantly influenced by oxygen density at the surface. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
11.
《化学:亚洲杂志》2017,12(20):2727-2733
Hydrogen production by catalytic water splitting using sunlight holds great promise for clean and sustainable energy source. Despite the efforts made in the past decades, challenges still exist in pursuing solid catalysts with light‐harvesting capacity, large surface areas and efficient utilities of the photogenerated carrier, at the same time. Here, a multiple structure design strategy leading to highly enhanced photocatalytic performance on hydrogen production from water splitting in Dion–Jacobson perovskites KCa2Nan ‐3Nbn O3n +1 is described. Specifically, chemical doping (N/Nb4+) of the parent oxides via ammoniation improved the ability of sunlight harvesting efficiently; subsequent liquid exfoliation of the doped perovskites yielded ultrathin [Ca2Nan ‐3Nbn O3n +1]− nanosheets with greatly increased surface areas. Significantly, the maximum hydrogen evolution appears in the n =4 nanosheets, which suggests the most favorable thickness for charge separation in such perovskite‐type catalysts. The optimized black N/Nb4+‐[Ca2NaNb4O13]− nanosheets show greatly enhanced photocatalytic performance, as high as 973 μmol h−1 with Pt loading, on hydrogen evolution from water splitting. As a proof‐of‐concept, this work highlights the feasibility of combining various chemical strategies towards better catalysts and precise thickness control of two‐dimensional materials. 相似文献
12.
《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2017,129(4):1125-1130
The design of complex heterostructured electrode materials that deliver superior electrochemical performances to their individual counterparts has stimulated intensive research on configuring supercapacitors with high energy and power densities. Herein we fabricate hierarchical tectorum‐like α‐Fe2O3/polypyrrole (PPy) nanoarrays (T‐Fe2O3/PPy NAs). The 3D, and interconnected T‐Fe2O3/PPy NAs are successfully grown on conductive carbon cloth through an easy self‐sacrificing template and in situ vapor‐phase polymerization route under mild conditions. The electrode made of the T‐Fe2O3/PPy NAs exhibits a high areal capacitance of 382.4 mF cm−2 at a current density of 0.5 mA cm−2 and excellent reversibility. The solid‐state asymmetric supercapacitor consisting of T‐Fe2O3/PPy NAs and MnO2 electrodes achieves a high energy density of 0.22 mWh cm−3 at a power density of 165.6 mW cm−3. 相似文献
13.
Novel synthesis of Fe2O3–Pt ellipsoids coated by double‐shelled La2O3 as a catalyst for the reduction of 4‐nitrophenol 下载免费PDF全文
Yan Gao Jiasheng Fang Yiwei Zhang Chao Zhang Shuo Zhao Yuming Zhou Mengqiu Huang Xiaoli Sheng 《应用有机金属化学》2018,32(3)
A facile strategy is reported for the fabrication of Pt‐loaded core–shell nanocomposite ellipsoids (Fe2O3‐Pt@DSL) consisting of ellipsoidal Fe2O3 cores, double‐layered La2O3 shells and deposited Pt nanoparticles (NPs). The formation of the doubled‐shelled structure uses Fe2O3‐Pt@mSiO2 as template sacrificial agent and it involves the re‐deposition of silica and self‐assembly of metal oxide units. The preparation methods of double‐shelled metal oxides avoid repeated coating and etching and could be utilized to fabricate other shaped double‐shelled composites. Characterization results indicated that the Fe2O3‐Pt@DSL nanocomposites possessed mesoporous structure and tunable shell thickness. Moreover, due to the formation of Fe2O3 and La2O3 composites, Pt NPs can also be stabilized via deposition on chemically active oxides with a synergistic effect. Therefore, as a catalyst for the reduction of 4‐nitrophenol, Fe2O3‐Pt@DSL showed superior catalytic activity and reusability due to structural superiority and enhanced composite synergy. Finally, well‐dispersed Pt NPs were encapsulated into the void between the shell layers to construct the Fe2O3‐Pt@DSL‐Pt catalyst. 相似文献
14.
Hans‐Jürgen Holdt Holger Müller Alexandra Kelling Hans‐Joachim Drexler Thomas Müller Thomas Schwarze Uwe Schilde Ines Starke 《无机化学与普通化学杂志》2006,632(1):114-122
Mercury(II) Chloride and Iodide Complexes of Dithia‐ and Tetrathiacrown Ethers The complexes [(HgCl2)2((ch)230S4O6)] ( 1 ), [HgCl2(mn21S2O5)] ( 2 ), [HgCl2(ch18S2O4)] ( 3 ) and [HgI(meb12S2O2)]2[Hg2I6] ( 4 ) have been synthesized, characterized and their crystal structures were determined. In [(HgCl2)2((ch)230S4O6)] two HgCl2 units are discretely bonded within the ligand cavity of the 30‐membered dichinoxaline‐tetrathia‐30‐crown‐10 ((ch)230S4O6) forming a binuclear complex. HgCl2 forms 1 : 1 “in‐cavity” complexes with the 21‐membered maleonitrile‐dithia‐21‐crown‐7 (mn21S2O5) ligand and the 18‐membered chinoxaline‐dithia‐18‐crown‐6 (ch18S2O4) ligand, respectively. The 12‐membered 4‐methyl‐benzo‐dithia‐12‐crown‐4 (meb12S2O2) ligand gave with two equivalents HgI2 the compound [HgI(meb12S2O2)]2[Hg2I6]. In the cation [HgI(meb12S2O2)]+ meb12S2O2 forms with the cation HgI+ a half‐sandwich complex. 相似文献
15.
Dr. Heng‐guo Wang De‐long Ma Yun Huang Prof. Dr. Xin‐bo Zhang 《Chemistry (Weinheim an der Bergstrasse, Germany)》2012,18(29):8987-8993
Porous V2O5 nanotubes, hierarchical V2O5 nanofibers, and single‐crystalline V2O5 nanobelts were controllably synthesized by using a simple electrospinning technique and subsequent annealing. The mechanism for the formation of these controllable structures was investigated. When tested as the cathode materials in lithium‐ion batteries (LIBs), the as‐formed V2O5 nanostructures exhibited a highly reversible capacity, excellent cycling performance, and good rate capacity. In particular, the porous V2O5 nanotubes provided short distances for Li+‐ion diffusion and large electrode–electrolyte contact areas for high Li+‐ion flux across the interface; Moreover, these nanotubes delivered a high power density of 40.2 kW kg?1 whilst the energy density remained as high as 201 W h kg?1, which, as one of the highest values measured on V2O5‐based cathode materials, could bridge the performance gap between batteries and supercapacitors. Moreover, to the best of our knowledge, this is the first preparation of single‐crystalline V2O5 nanobelts by using electrospinning techniques. Interestingly, the beneficial crystal orientation provided improved cycling stability for lithium intercalation. These results demonstrate that further improvement or optimization of electrochemical performance in transition‐metal‐oxide‐based electrode materials could be realized by the design of 1D nanostructures with unique morphologies. 相似文献
16.
Ling Xie Yan Yan Huijuan Lin Kun Rui Aoming Huang Min Du Yu Shen Jixin Zhu 《化学:亚洲杂志》2020,15(7):1105-1109
Owing to the high specific capacity and energy density, metal oxides have become very promising electrodes for lithium‐ion batteries (LIBs). However, poor electrical conductivity accompanied with inferior cycling stability resulting from large volume changes are the main obstacles to achieve a high reversible capacity and stable cyclability. Herein, a facile and general approach to fabricate SnO2, Fe2O3 and Fe2O3/SnO2 fibers is proposed. The appealing structural features are favorable for offering a shortened lithium‐ion diffusion length, easy access for the electrolyte and reduced volume variation when used as anodes in LIBs. As a consequence, both single and hybrid oxides show satisfactory reversible capacities (1206 mAh g?1 for Fe2O3 and 1481 mAh g?1 for Fe2O3/SnO2 after 200 cycles at 200 mA g?1) and long lifespans. 相似文献
17.
Ming Qin Di Lan Jiaolong Liu Hongsheng Liang Limin Zhang Hui Xing Tingting Xu Hongjing Wu 《Chemical record (New York, N.Y.)》2020,20(2):102-119
Multi‐shelled hollow spheres metal oxides, namely materials with more than three shells, have attracted increasing attention due to their unique structure. The preparation methods of typical metal oxides including NiO, Co3O4 and ZnO etc. have been summarized in this review. Simultaneously, the parameters that influence the ultimate morphologies, shell number as well as the compositions have also been discussed. The potential application fields in energy conversion and storage, electromagnetic wave absorption, photocatalysis that related to the unique structure are also highlighted. Finally, the future researches of multi‐shelled hollow spheres metal oxides are further discussed. 相似文献
18.
Realizing both High Energy and High Power Densities by Twisting Three Carbon‐Nanotube‐Based Hybrid Fibers 下载免费PDF全文
Ye Zhang Yang Zhao Dr. Xunliang Cheng Dr. Wei Weng Jing Ren Xin Fang Yishu Jiang Peining Chen Zhitao Zhang Prof. Yonggang Wang Prof. Huisheng Peng 《Angewandte Chemie (International ed. in English)》2015,54(38):11177-11182
Energy storage devices, such as lithium‐ion batteries and supercapacitors, are required for the modern electronics. However, the intrinsic characteristics of low power densities in batteries and low energy densities in supercapacitors have limited their applications. How to simultaneously realize high energy and power densities in one device remains a challenge. Herein a fiber‐shaped hybrid energy‐storage device (FESD) formed by twisting three carbon nanotube hybrid fibers demonstrates both high energy and power densities. For the FESD, the energy density (50 mWh cm?3 or 90 Wh kg?1) many times higher than for other forms of supercapacitors and approximately 3 times that of thin‐film batteries; the power density (1 W cm?3 or 5970 W kg?1) is approximately 140 times of thin‐film lithium‐ion battery. The FESD is flexible, weaveable and wearable, which offers promising advantages in the modern electronics. 相似文献
19.
Ming Zhao Kun Cao Mengjia Liu Jing Zhang Rong Chen Qinyuan Zhang Zhiguo Xia 《Angewandte Chemie (International ed. in English)》2020,59(31):12938-12943
The stability of luminescent materials is a key factor for the practical application in white light‐emitting diodes (LEDs). Poor chemical stability of narrow‐band green‐emitting RbLi(Li3SiO4)2:Eu2+ (RLSO:Eu2+) phosphor hinders their further commercialization even if they have excellent stability against thermal quenching. Herein, we propose an efficient protection scheme by combining the surface coating of amorphous Al2O3 and hydrophobic modification by octadecyltrimethoxysilane (ODTMS) to construct the moisture‐resistant dual‐shelled RLSO:Eu2+@Al2O3@ODTMS composite. The growth mechanisms of both the Al2O3 inorganic layer and the silane organic layer on the phosphor surface are investigated. The results remarkably improve the water‐stability of this narrow‐band green emitter. The evaluation of the white LED by employing this composite as the green component demonstrates that RLSO:Eu2+@Al2O3@ODTMS is a promising candidate for the high‐performance display backlights, and this dual‐shelled strategy provides an alternative method to improve the moisture‐resistant property of humidity‐sensitive phosphors. 相似文献
20.
Exploring noble‐metal‐free, highly active and durable catalysts is vital to get to grips with the energy and environmental issues. Herein, we first dexterously design and synthesize a class of ternary Nb6/CZS/g‐CN photocatalysts for the removal of hexavalent chromium Cr (VI) and organic dye pollutant (MO) from wastewater under visible‐light irradiation. A heterojunction Nb6–1/CZS/g‐CN loaded with 0.01 g K7HNb6O19 showed excellent photocatalytic performance, with the MO photodegradation efficiency of 94% in 1 h and the Cr (VI) (150 mg/l) photoreduction efficiency as high as 91% in 2 hr. The main active species were deemed to be O2.‐. Additionally, the as‐prepared ternary heterojunction exhibits superior hydrogen evolution reaction (HER) rate. A heterojunction Nb6–4/CZS/g‐CN loaded with 0.5 g K7HNb6O19 exhibited the highest H2 evolution rate as high as 1777.86 μmol h?1 g?1 under visible‐light illumination, which is increased to 5.7 and 2.7 times that of bare CZS and biphase heterojunction CZS/g‐CN. These findings afford a new class of promising low‐cost photocatalyst bodying for its huge potential value in sustainable energy development and wastewater treatment. 相似文献