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161.
Potassium‐Ion Battery Anode Materials Operating through the Alloying–Dealloying Reaction Mechanism
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Irin Sultana Md Mokhlesur Rahman Ying Chen Alexey M. Glushenkov 《Advanced functional materials》2018,28(5)
Anode materials that operate via the alloying–dealloying reaction mechanism are well known in established and maturing battery systems such as lithium‐ion and sodium‐ion batteries. Recently, a new type of metal‐ion battery that utilizes K+ ions in its operating principle has attracted significant attention due to a possibility of building high voltage cells using an abundant potassium ionic shuttle. Establishing promising electrode materials is of paramount importance for this new type of battery. This feature article summarizes available early results on the alloying–dealloying anode materials in potassium electrochemical cells. Based on original research (some data are presented for the first time) and independently published literature, experimental results on silicon, tin, phosphorus, antimony, and lead‐containing anodes are critically discussed. The electrochemical properties, charge storage mechanisms, and achievable capacities are considered. The results are compared with the behaviors of the same materials in lithium and sodium cells, and the importance of the volumetric parameters of electrodes is emphasized. Finally, a number of further research directions in these interesting anode materials are suggested. The feature article provides a useful reference for the growing number of researchers and specialists working in the field of emerging metal‐ion batteries with non‐lithium chemistries. 相似文献
162.
Avdeeva Yuliya Luzhkova Irina Ermakov Alexey Samigullina Rina Vovkotrub Emma Dobrinsky Edward Zainulin Yuri 《Metallurgical and Materials Transactions B》2020,51(3):1048-1059
Metallurgical and Materials Transactions B - In this work, the thermal studies of ultrafine and nanocrystalline core–shell structures of Ti(Mo)C and Ti(Mo)C-Co formed in the process of plasma... 相似文献
163.
Tokarev A Aprelev A Zakharov MN Korneva G Gogotsi Y Kornev KG 《The Review of scientific instruments》2012,83(6):065110
We report on the development of a multifunctional magnetic rotator that has been built and used during the last five years by two groups from Clemson and Drexel Universities studying the rheological properties of microdroplets. This magnetic rotator allows one to generate rotating magnetic fields in a broad frequency band, from hertz to tens kilohertz. We illustrate its flexibility and robustness by conducting the rheological studies of simple and polymeric fluids at the nano and microscale. First we reproduce a temperature-dependent viscosity of a synthetic oil used as a viscosity standard. Magnetic rotational spectroscopy with suspended nickel nanorods was used in these studies. As a second example, we converted the magnetic rotator into a pump with precise controlled flow modulation. Using multiwalled carbon nanotubes, we were able to estimate the shear modulus of sickle hemoglobin polymer. We believe that this multifunctional magnetic system will be useful not only for micro and nanorheological studies, but it will find much broader applications requiring remote controlled manipulation of micro and nanoobjects. 相似文献
164.
Andrei L. Lyubimtsev Alexey I. Baranov Andreas Fischer Lars Kloo Boris A. Popovkin 《Journal of Alloys and Compounds》2002,340(1-2):167-172
The electronic structure of Ni3Sn was calculated at ab initio levels for the crystal structure of the low-temperature modification of Ni3Sn refined upon data of single-crystal X-ray diffractometry (P63/mmc, a=5.2950(7), c=4.247(1) Å, R=0.0288). The calculations were made with the use of fixed Gaussian (CRYSTAL98 software) and energy-dependent (Stuttgart TB-LMTO-ASA software) basis sets. Difference electron charge density maps were analysed and compared with that of a hypothetical hcp Ni in order to understand bonding in Ni3Sn. It was found that bonding in Ni3Sn has multicentre character with Ni–Sn interaction stronger than Ni–Ni one. 相似文献
165.
Huaxi Bao Minyong Du Hui Wang Kai Wang Xiaokun Zuo Fangyv Liu Lu Liu Dominik Eder Alexey Cherevan Shimin Wang Li Wan Shuai Zhao Shengzhong Liu 《Advanced functional materials》2021,31(34):2102452
Hole transport layers (HTLs) play a key role in perovskite solar cells (PSCs), particularly in the inverted PSCs (IPSCs) that demand more in its stability. In this study, samarium-doped nickel oxide (Sm:NiOx) nanoparticles are synthesized via a chemical precipitation method and deposited as a hole transport layer in the IPSCs. Sm3+ doping can reduce the formation energy of Ni vacancy and naturally increase the density of Ni vacancies, thereby rendering increased hole density. Thenceforth, the electronic conductivity is enhanced significantly, and work function enlarged in the Sm:NiOx film in favor of extracting holes and suppressing charge recombination. Consequently, the Sm:NiOx-based IPSCs attain outstanding power conversion efficiencies as high as 20.71%. Even when it is applied in flexible solar cells, it still outputs efficiency as high as 17.95%. More importantly, the Sm:NiOx is compatible with large-scale processing whereby the large area IPSCs of 1.0 cm2 and 40 × 40 mm2 deliver high efficiencies of 18.51% and 15.27%, respectively, all are among the highest for the inorganic HTLs based IPSCs. This research demonstrates that, while revealing the doping effect in depth, Sm:NiOx can be a promising hole transport material for fabricating efficient, large-area, and flexible IPSCs in the future. 相似文献
166.
Nataliia S. Vorobeva Alexey Lipatov Angel Torres Jun Dai Jehad Abourahma Duy Le Archit Dhingra Simeon J. Gilbert Pavlo V. Galiy Taras M. Nenchuk Dmitry S. Muratov Talat S. Rahman Xiao Cheng Zeng Peter A. Dowben Alexander Sinitskii 《Advanced functional materials》2021,31(52):2106459
Theoretical and experimental investigations of various exfoliated samples taken from layered In4Se3 crystals are performed. In spite of the ionic character of interlayer interactions in In4Se3 and hence much higher calculated cleavage energies compared to graphite, it is possible to produce few-nanometer-thick flakes of In4Se3 by mechanical exfoliation of its bulk crystals. The In4Se3 flakes exfoliated on Si/SiO2 have anisotropic electronic properties and exhibit field-effect electron mobilities of about 50 cm2 V−1 s−1 at room temperature, which are comparable with other popular transition metal chalcogenide (TMC) electronic materials, such as MoS2 and TiS3. In4Se3 devices exhibit a visible range photoresponse on a timescale of less than 30 ms. The photoresponse depends on the polarization of the excitation light consistent with symmetry-dependent band structure calculations for the most expected ac cleavage plane. These results demonstrate that mechanical exfoliation of layered ionic In4Se3 crystals is possible, while the fast anisotropic photoresponse makes In4Se3 a competitive electronic material, in the TMC family, for emerging optoelectronic device applications. 相似文献
167.
Peter B. Mozhaev Julia E. Mozhaeva Alexey V. Khoryushin Alexey V. Puriy Jørn Bindslev Hansen Claus S. Jacobsen 《Journal of Superconductivity and Novel Magnetism》2017,30(7):1781-1794
A deposition process for NdBa2Cu3O y thin films by laser ablation at decreased deposition temperature was developed using substitution of oxygen with argon in the chamber during deposition. A low deposition rate is the crucial factor to obtain high-quality NBCO films. The Nd/Ba cation disorder in the film can be suppressed by an increase of the deposition temperature or by a decrease of the oxygen partial pressure during deposition. The presence of Nd/Ba disorder during deposition stimulates the introduction of oxygen into the growing film. A simple model is proposed for estimation of oxygen contents in the film using structural parameters measured with XRD techniques. Studies of the post-deposition annealing process showed ordering of the Nd/Ba sub-lattice and intense oxygen in- and out-diffusion. The temperature of the post-deposition annealing step should be chosen low enough (~400 °C) to avoid oxygen diffusion out of the NBCO film. 相似文献
168.
Metasurfaces: Enhancement of Magnetic Resonance Imaging with Metasurfaces (Adv. Mater. 9/2016)
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169.
Dr. Alexey Raykov Dr. Sergey Salikeev Dr. Aleksey Burmistrov Dr. Marina Fomina 《真空研究与实践》2016,28(3):43-47
Experimental study of pumping characteristics of a pilot model of a claw single‐stage vacuum pump with identical rotors was carried out. The curves of pumping speed vs. pressure at different rotary speed and the ultimate pressure at different rotors speed were determined on a test unit. Indicator pressure diagrams in working chambers of claw vacuum pump were obtained with the help of special sensors. Thus, an experimental data bank concerning the pumping characteristics of claw vacuum pump was created. It may be used for estimation of mathematical model adequacy and further development of the pump design. 相似文献
170.
Pawel Mierczynski Sergey V. Dubkov Sergey V. Bulyarskii Alexander A. Pavlov Sergey N. Skorik Alexey Yu Trifonov Agnieszka Mierczynska Eugene P. Kitsyuk Sergey A. Gavrilov Tomasz P. Maniecki Dmitry G. Gromov 《材料科学技术学报》2018,34(3):472-480
Carbon nanotube(CNT) arrays were fabricated on Ct-Me-N-(O) alloys with content of Ct in the range of 6–40 at.% by chemical vapour deposition. The Ct was a catalytic metal from the group of the following elements: Ni, Co, Fe, Pd, while Me was a transition metal from the group of Ⅳ–Ⅶ of the periodic table(where Me = Ti, V, Cr, Zr, Nb, Mo, Ta, W, Re). Carbon nanotubes were found to grow efficiently on the alloy surface with its composition containing Ti, V, Cr, Zr, Hf, Nb or Ta. The growth of CNTs was not observed when the alloy contained W or Re. Additions of oxygen and nitrogen in the alloy facilitated the formation of oxynitrides and catalyst extrusion on the alloy surface. Replacement of the metals in alloy composition affected the diameter of the resulting CNTs. The obtained results showed that the alloy films of varying thickness(10–500 nm) may be used for the CNTs growth. The resulting CNT material was highly homogenous and its synthesis reproducible. 相似文献