Browsing by Author "Zhang, L"

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    Constructing “Li-rich Ni-rich” oxide cathodes for high-energy-density Li-ion batteries
    (Royal Society of Chemistry, 2023-01-26) Li, B; Rousse, G; Zhang, L; Avdeev, M; Deschamps, M; Abakumov, AM; Tarascon, JM
    The current exploration of high-energy-density cathode materials for Li-ion batteries is mainly concentrated on either so-called “Li-rich” or “Ni-rich” oxides. However, both are suffering from formidable practical challenges. Here, we combine these two concepts to obtain “Li-rich Ni-rich” oxides in pursuit of more practical high-energy-density cathodes. As a proof of concept, we synthesized an array of Li1+yNi(3−5y)/3Mo2y/3O2 oxides, whose structures were identified to be the coexistence of LiNiO2-rich and Li4MoO5-rich domains with the aid of XRD, TEM, and NMR techniques. Such an intergrowth structure of 5–20 nm size enables excellent mechanical and structural reversibility for the layered rock-salt LiNiO2-rich domain upon cycling thanks to the robust cubic rock-salt Li4MoO5-rich domain enabling an “epitaxial stabilization” effect. As a result, we achieved high capacities (>220 mA h g−1) with Ni contents as low as 80%; the Li1.09Ni0.85Mo0.06O2 member (y = 0.09) shows much improved cycling performances (91% capacity retention for 100 cycles at C/10) compared with pure LiNiO2. This work validates the feasibility of constructing Li-rich Ni-rich compounds in the form of intergrowing domains and hence unlocks vast possibilities for future cathode design. © The Royal Society of Chemistry
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    Controlled one‐pot synthesis of nickel single atoms embedded in carbon nanotube and graphene supports with high loading
    (Wiley, 2020-04-09) Zhao, S; Wang, T; Zhou, G; Zhang, L; Lin, C; Veder, JP; Johannessen, B; Saunders, M; Yin, L; Liu, C; De Marco, R; Yang, SZ; Zhang, Q; Jiang, SP
    Single‐atom catalysts (SACs) have attracted much attentions due to the advantages of high catalysis efficiency and selectivity. However, the controllable and efficient synthesis of SACs remains a significant challenge. Herein, we report a controlled one‐pot synthesis of nickel single atoms embedded on nitrogen‐doped carbon nanotubes (NiSA−N−CNT) and nitrogen‐doped graphene (NiSA−N−G). The formation of NiSA−N−CNT is due to the solid‐to‐solid rolling up mechanism during the high temperature pyrolysis at 800 °C from the stacked and layered Ni‐doped g‐C3N4, g‐C3N4−Ni structure to a tubular CNT structure. Addition of citric acid introduces an amorphous carbon source on the layered g‐C3N4−Ni and after annealing at the same temperature of 800 °C, instead of formation of NiSA−N−CNT, Ni single atoms embedded in planar graphene type supports, NiSA−N−G were obtained. The density functional theory (DFT) calculation indicates the introduction of amorphous carbon source substantially reduces the structure fluctuation or curvature of layered g‐C3N4‐Ni intermediate products, thus interrupting the solid‐to‐solid rolling process and leading to the formation of planar graphene type supports for Ni single atoms. The as‐synthesized NiSA−N−G with Ni atomic loading of ∼6 wt% catalysts shows a better activity and stability for the CO2 reduction reaction (CO2RR) than NiSA−N−CNT with Ni atomic loading of ∼15 wt% due to the open and exposed Ni single atom active sites in NiSA−N−G. This study demonstrates for the first time the feasibility in the control of the microstructure of carbon supports in the synthesis of SACs. © 1999-2024 John Wiley & Sons, Inc or related companies. All rights reserved.
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    GumTree - an integrated scientific experiment environment
    (Elsevier B. V., 2005-11-15) Lam, T; Hauser, N; Götz, A; Hathaway, PV; Franceschini, F; Rayner, H; Zhang, L
    GumTree is an open source and multi-platform graphical user interface for performing neutron scattering and X-ray experiments. It handles the complete experiment life cycle from instrument calibration, data acquisition, and real time data analysis to results publication. The aim of the GumTree Project is to create a highly Integrated Scientific Experiment Environment (ISEE), allowing interconnectivity and data sharing between different distributed components such as motors, detectors, user proposal database and data analysis server. GumTree is being adapted to several instrument control server systems such as TANGO, EPICS and SICS, providing an easy-to-use front-end for users and simple-to-extend model for software developers. The design of GumTree is aimed to be reusable and configurable for any scientific instrument. GumTree will be adapted to six neutron beam instruments for the OPAL reactor at ANSTO. Other European institutes including ESRF, ILL and PSI have shown interest in using GumTree as their workbench for instrument control and data analysis. © 2006 Elsevier B.V.
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    GumTree - an integrated scientific experiment environment
    (The Bragg Institute, Australian Nuclear Science and Technology Organisation, 2005-11-27) Lam, T; Hauser, N; Götz, A; Hathaway, PV; Franceschini, F; Rayner, H; Zhang, L
    GumTree is an open source and multi-platform graphical user interface for performing neutron scattering and X-ray experiments. It handles the complete experiment life cycle from instrument calibration, data acquisition, and real time data analysis to results publication. The aim of the GumTree Project is to create a highly Integrated Scientific Experiment Environment (ISEE), allowing interconnectivity and data sharing between different distributed components such as motors, detectors, user proposal database and data analysis server. GumTree is being adapted to several instrument control server systems such as TANGO, EPICS and SICS, providing an easy-to-use front-end for users and simple-to-extend model for software developers. The design of GumTree is aimed to be reusable and configurable for any scientific instrument. GumTree will be adapted to six neutron beam instruments for the OPAL reactor at ANSTO. Other European institutes including ESRF, ILL and PSI have shown interest in using GumTree as their workbench for instrument control and data analysis. © 2005 The Authors
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    High/low-moment phase transition in hexagonal Mn-Fe-P-Si compounds
    (American Physical Society, 2012-07-30) Dung, NH; Zhang, L; Ou, ZQ; Zhao, L; van Eijck, L; Mulders, AM; Avdeev, M; Suard, E; van Dijk, NH; Brück, E
    Using high-resolution neutron diffraction measurements for Mn-rich hexagonal Mn-Fe-P-Si compounds, we show that the substitution of Mn for Fe on the 3f sites results in a linear decrease of the Fe/Mn(3f) magnetic moments, while the Mn(3g) magnetic moments remain constant. With increasing temperature, the Mn(3g) magnetic moments show almost no change, while the Fe/Mn(3f) moments decrease quickly when the transition temperature is approached. The reduction of the magnetic moments at the transition temperature and in the high-temperature range is discussed based on changes in interatomic distances and lattice parameters and high-temperature magnetic-susceptibility measurement. © 2012, American Physical Society.
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    Neutron diffraction study on the magnetic structure of Fe2P-based Mn0.66Fe1.29P1-xSix melt-spun ribbons
    (Elsevier Science BV., 2013-08-01) Ou, ZQ; Zhang, L; Dung, NH; van Eijck, L; Mulders, AM; Avdeev, M; van Dijk, NH; Brück, E
    We report on the magnetic and structural properties of Mn0.66Fe1.29P1−xSix melt-spun ribbons with 0.34≤x≤0.42 that are promising candidates for high-temperature magnetocaloric applications. A magnetic moment of up to 4.57 μB/f.u. for x=0.34 indicates high magnetic density in the system, which is certainly advantageous for the magnetocaloric effects. Introducing site disorder at the 3g site by replacing 1/3 of Fe with Mn appears to enhance the magnetic interaction, while the strong magnetoelastic coupling is maintained. This site disorder also shows a stabilizing effect on the hexagonal crystal structure, which is maintained to a high Si content. The moment alignment within the crystallographic unit cell is also affected when the Si content is increased from x=0.34 to 0.42 in the Mn0.66Fe1.29P1−xSix compounds as the canting angle with respect to the c-direction increases. © 2013, Elsevier Ltd.
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    Novel low-strain layered/rocksalt intergrown cathode for high-energy Li-ion batteries
    (American Chemical Society (ACS), 2023-11-16) Xu, L; Chen, S; Su, Y; Shen, X; He, J; Avdeev, M; Kan, WH; Zhang, B; Fan, W; Chen, L; Cao, D; Lu, Y; Wang, L; Wang, M; Bao, L; Zhang, L; Li, N; Wu, F
    Both layered- and rocksalt-type Li-rich cathode materials are drawing great attention due to their enormous capacity, while the individual phases have their own drawbacks, such as great volume change for the layered phase and low electronic and ionic conductivities for the rocksalt phase. Previously, we have reported the layered/rocksalt intergrown cathodes with nearly zero-strain operation, while the use of precious elements hinders their industrial applications. Herein, low-cost 3d Mn4+ ions are utilized to partially replace the expensive Ru5+ ions, to develop novel ternary Li-rich cathode material Li1+x[RuMnNi]1-xO2. The as-designed Li1.15Ru0.25Mn0.2Ni0.4O2 is revealed to have a layered/rock salt intergrown structure by neutron diffraction and transmission electron microscopy. The as-designed cathode exhibits ultrahigh lithium-ion reversibility, with 0.86 (231.1 mAh g-1) out of a total Li+ inventory of 1.15 (309.1 mAh g-1). The X-ray absorption spectroscopy and resonant inelastic X-ray scattering spectra further demonstrate that the high Li+ storage of the intergrown cathode is enabled by leveraging cationic and anionic redox activities in charge compensation. Surprisingly, in situ X-ray diffraction shows that the intergrown cathode undergoes extremely low-strain structural evolution during the charge-discharge process. Finally, the Mn content in the intergrown cathodes is found to be tunable, providing new insights into the design of advanced cathode materials for high-energy Li-ion batteries. © 2024 American Chemical Society.
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    Status of the compactlight design study
    (JACoW Publishing, 2019-05-19) D'Auria, G; Mitri, SD; Rochow, RA; Latina, A; Liu, X; Rossi, C; Schulte, D; Stapnes, S; Wu, X; Castañeda Cortes, HM; Clarke, J; Dunning, DJ; Thompson, N; Fang, W; Gazis, E; Gazis, N; Tanke, E; Trachnas, E; Goryashko, V; Jacewicz, M; Ruber, R; Taylor, G; Dowd, RT; Zhu, D; Aksoy, A; Nergiz, Z; Apsimon, R; Burt, G; Castilla, A; Priem, H; Janssen, X; Luiten, J; Mutsaers, P; Stragier, X; Alesini, D; Bellaveglia, M; Buonomo, B; Cardelli, F; Croia, M; Diomede, M; Ferrario, M; Gallo, A; Giribono, A; Piersanti, L; Scifo, J; Spataro, B; Vaccarezza, C; Geometrante, R; Kokole, M; Arnesano, J; Bosco, F; Ficcadenti, L; Mostacci, A; Palumbo, L; Dattoli, G; Nguyen, F; Petralia, A; Marcos, J; Marín, E; Muñoz Horta, R; Perez, F; Faus-Golfe, A; Han, Y; Bernhard, A; Gethmann, J; Calvi, M; Schmidt, T; Zhang, K; Esperante, D; Fuster, J; Gimeno, B; Gonzalez-Iglesias, D; Aicheler, M; Hoekstra, R; Cross, AW; Nix, L; Zhang, L
    CompactLight (XLS) is an International Collaboration of 24 partners and 5 third parties, funded by the European Union through the Horizon 2020 Research and Innovation Programme. The main goal of the project, which started in January 2018 with a duration of 36 months, is the design of an hard X-ray FEL facility beyond today’s state of the art, using the latest concepts for bright electron photo-injectors, high-gradient accelerating structures, and innovative shortperiod undulators. The specifications of the facility and the parameters of the future FEL are driven by the demands of potential users and the associated science cases. In this paper we will give an overview on the ongoing activities and the major results achieved until now. © The Authors - CC-BY 3.0 licence
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    Ultralow loss and high tunability in a non‐perovskite relaxor ferroelectric
    (Wiley, 2022-11-10) Li, R; Xu, D; Avdeev, M; Zhang, L; Chen, XF; Gou, GY; Wang, D; Liu, WF; Zhou, D
    Dielectric ceramics are fundamental for electronic systems, including energy storages, microwave applications, ultrasonics, and sensors. Relaxor ferroelectrics show superb performance among dielectrics due to their high efficiency and energy density by the nature of nanodomains. Here, a novel non‐perovskite relaxor ferroelectric, Bi6Ti5WO22, with ultralow loss, ≈10−3, highly tunable permittivity, ≈2200 at room temperature with 40% tunability and the superparaelectric region at room temperature is presented. The actual crystal structure and the nanodomains of Bi6Ti5WO22 are demonstrat Various‐temperature neutron powder diffraction and in situ high‐resolution transmission‐electron‐microscopy illustrate the twinning effect, subtle structure change and micro‐strain in the material influenced by temperature, manifesting the actual crystal structure of Bi6Ti5WO22. Compared with dielectric loss of BaTiO3‐based dielectric tunable materials, the loss of Bi6Ti5WO22 is more than an order of magnitude lower, which makes it exhibit a figure of merit (≈240), much higher than that of conventional dielectric tunable materials (< 100), endorse the material great potential for direct applications. The present research offers a strategy for discovering novel relaxor ferroelectrics and a highly desirable material for fabricating energy storage capacitors, microwave dielectrics, and ultrasonics. © 1999-2024 John Wiley & Sons, Inc