The uncontrollable Li electrostripping and plating process that results in dendritic Li growth and huge volume change of Li anode limits the practicality of Li metal batteries(LMBs).To simultaneously address these iss...The uncontrollable Li electrostripping and plating process that results in dendritic Li growth and huge volume change of Li anode limits the practicality of Li metal batteries(LMBs).To simultaneously address these issues,designing three-dimensional(3D),lithiophilic and mechanically robust electrodes seems to be one of the cost-effective strategies.Herein,a new 3D Li-B-C-Al alloy anode is designed and fabricated.The prepared 3D alloy anode exhibits not only superior lithiophilicity that facilitates uniform Li nucleation and growth but also sufficient mechanical stability that maintains its structural integrity.Superior performance of the prepared 3D alloy is demonstrated through comprehensive electrochemical tests.In addition,non-destructive and 3D synchrotron X-ray computed tomography(SX-CT)technique is employed to investigate the underlying working mechanisms of the prepared alloy anode.A unique twofold Li electrostripping and plating mechanism under different electrochemical cycling conditions is revealed.Lastly,improved performance of the full cells built with the 3D alloy anode and LiNi_(0.8)Co_(0.1)Mn_(0.1)O_(2)(NCM811)cathode corroborate its potential application capability.Overall,the current work not only showcases the superiority of the 3D alloy as potential anode material for LMBs but also provides fundamental insights into its underlying working mechanisms that may further propel its research and development.展开更多
The early Cambrian pentamerous microfossil Olivooides/Punctatus in South China, which is characterized by a diagnostic stellate tubular apex, has been well-known for its almost complete development sequence that can b...The early Cambrian pentamerous microfossil Olivooides/Punctatus in South China, which is characterized by a diagnostic stellate tubular apex, has been well-known for its almost complete development sequence that can be confidently traced from embryos and hatched juveniles, to conical adults. However, its zoological affinity remains highly controversial. Here we describe the internal microanatomic structures of the soft-body inside the peridermal theca of Olivooides multisulcatus Qian, 1977, including interradial pairs of tentacles, adradial and perradial frenula, perradial oral marginal lappets and twins of perradial gastric saccule-like humps as well as a circular velarium with striated coronal muscles. Particularly, one specimen shows bifurcated velarial canals along the bell aperture. Both the components of the soft-body and the external theca (or cyst) are arranged in perfect pentaradial symmetry. These characteristics are more compatible with those of living cubomedusans and co-occurring Cambrian athecate embryonic cubozoans. Concerning the presence of peridermal theca, Olivooides most likely represents an extinct thecate stem-group cubomedusae but devoid of both perradial eyes and specialized pedalia. The well-grown soft body inside the peridermal tube displays a set of mixed features of both polyp and medusa.展开更多
Lead dissolved in water must be removed in order not to cause diseases, especially from high pH aqueous solution. Various oxides having high specific surface area are often applied to remove lead in water media. To im...Lead dissolved in water must be removed in order not to cause diseases, especially from high pH aqueous solution. Various oxides having high specific surface area are often applied to remove lead in water media. To improve removal ability for lead species, it is necessary to understand the adsorbed structure of lead species on oxides. At first, the adsorption behavior of lead from high pH solution in the presence of Ca<sup>2+</sup> and Na+ was compared. Lead and calcium species were adsorbed up to the monolayer, and the adsorption isotherm was analyzed as Langmuir-type adsorption. In the presence of Ca<sup>2+</sup>, the amount of removed lead was reduced. To clarify this influence of Ca<sup>2+</sup>, X-ray absorption spectroscopy was adopted. It was for the first time revealed that lead species at pH > 12 and pH < 10.5 differed, and that lead species adsorbed on various oxides had a similar structure.展开更多
Synchrotron radiation x-ray diffraction investigations of iron(Fe)and nickel(Ni)are conducted at pressures up to 354 and 368 GPa,respectively,and the equations of state(EOSs)at 298 K for the two elements are obtained ...Synchrotron radiation x-ray diffraction investigations of iron(Fe)and nickel(Ni)are conducted at pressures up to 354 and 368 GPa,respectively,and the equations of state(EOSs)at 298 K for the two elements are obtained for data extending to pressures as high as those at the center of the Earth,using the latest Pt-EOS pressure scale.From a least-squares fit to the Vinet equation using the observed pressure–volume data,the isothermal bulk modulus K0 and its pressure derivative K′0 are estimated to be 159.27(99)GPa and 5.86(4)for hcp-Fe,and 173.5(1.4)GPa and 5.55(5)for Ni.By comparing the present EOSs and extrapolated EOSs reported in the literature for Fe and Ni,the volumes of Fe and Ni at 365 GPa are found to be 2.3%and 1.5%larger than those estimated from extrapolated EOSs in previous studies,respectively.It is concluded that these discrepancies are due to the pressure scale.The present results suggest that the densities of Fe and Ni at a pressure of 365 GPa corresponding to the center of the Earth are 2.3%and 1.5%,respectively,lower than previously thought.展开更多
With exceptional capacity during high-voltage cycling,P3-type Nadeficient layered oxide cathodes have captured substantial attention.Nevertheless,they are plagued by severe capacity degradation over cycling.In this st...With exceptional capacity during high-voltage cycling,P3-type Nadeficient layered oxide cathodes have captured substantial attention.Nevertheless,they are plagued by severe capacity degradation over cycling.In this study,tuning and optimizing the phase composition in layered oxides through Li incorporation are proposed to enhance the high-voltage stability.The structural dependence of layered Na_(2/3)LixNi_(0.25)Mn_(0.75)O_(2)þδoxides on the lithium content(0.0≤x≤1.0)offered during synthesis is investigated systematically on an atomic scale.Surprisingly,increasing the Li content triggers the formation of mixed P2/O3-type or P3/P2/O3-type layered phases.As the voltage window is 1.5-4.5 V,P3-type Na2/3Ni_(0.25)Mn_(0.75)O_(2)(NL0.0NMO,R3m)material exhibits a sequence of phase transformations throughout the process of(de)sodiation,that is,O3⇌P3⇌O30⇌O3″.Such complicated phase transitions can be effectively suppressed in the Na2/3Li_(0.7)Ni_(0.25)Mn_(0.75)O_(2.4)(NL_(0.7)NMO)oxide with P2/P3/O3-type mixed phases.Consequently,cathodes made of NL0.7NMO exhibit a substantially enhanced cyclic performance at high voltages compared to that of the P3-type layered NL0.0NMO cathode.Specifically,NL0.7NMO demonstrates an outstanding capacity retention of 98%after 10 cycles at 1 C within 1.5-4.5 V,much higher than that of NL0.0NMO(83%).This work delves into the intricate realm of bolstering the high-voltage durability of layered oxide cathodes,paving the way for advanced sodium-ion battery technologies.展开更多
High-performance all-solid-state lithium-ion batteries require observation,control,and optimization of the electrode structure.X-ray computational tomography(CT)is an effective nondestructive method for observing the ...High-performance all-solid-state lithium-ion batteries require observation,control,and optimization of the electrode structure.X-ray computational tomography(CT)is an effective nondestructive method for observing the electrode structure in three dimensions.However,the limited availability of synchrotron radiation CT,which offers high-resolution imaging with a high signal-to-noise ratio,makes it difficult to conduct experiments and restricts the use of X-ray CT in battery development.Conversely,laboratory CT systems are widely available,but they use X-rays emitted from a metal target,resulting in lower image quality and resolution compared with synchrotron radiation CT.This study explores a method for achieving comparable resolution in laboratory CT images of all-solid-state batteries to that of synchrotron radiation CT.Our method involves using the synchrotron radiation CT images as training data for machine learning super-resolution.The results demonstrate that,by employing an appropriate machine learning algorithm and activation function,along with a sufficiently deep network,the image quality of laboratory CT becomes equivalent to that of synchrotron radiation CT.展开更多
Simultaneous ultrasonic elastic wave velocity and in situ synchrotron X-ray measurements on grossular garnet were carried out up to 17 GPa and 1 650 K. P- and S-wave vdoeities and bulk and shear modulus showed linear ...Simultaneous ultrasonic elastic wave velocity and in situ synchrotron X-ray measurements on grossular garnet were carried out up to 17 GPa and 1 650 K. P- and S-wave vdoeities and bulk and shear modulus showed linear pressure and temperature dependence. These data yielded a pressure derivative of the bulk modulus of 4.42(7) and a shear modulus of 1.27(3), which are in good agreement with those of garnets with variable chemical compositions. Temperature dependence of the bulk modulus of grossular (-1.36×10^-2 GPafK) is also similar to that of other garnets, while the temperature dependence of the shear modulus of grossular (-1.11×10^-2 GPa/K) is higher than those of magnesium end-member garnets and pyrolitic garnet.展开更多
基金supported by the National Natural Science Foundation of China(U1904216).
文摘The uncontrollable Li electrostripping and plating process that results in dendritic Li growth and huge volume change of Li anode limits the practicality of Li metal batteries(LMBs).To simultaneously address these issues,designing three-dimensional(3D),lithiophilic and mechanically robust electrodes seems to be one of the cost-effective strategies.Herein,a new 3D Li-B-C-Al alloy anode is designed and fabricated.The prepared 3D alloy anode exhibits not only superior lithiophilicity that facilitates uniform Li nucleation and growth but also sufficient mechanical stability that maintains its structural integrity.Superior performance of the prepared 3D alloy is demonstrated through comprehensive electrochemical tests.In addition,non-destructive and 3D synchrotron X-ray computed tomography(SX-CT)technique is employed to investigate the underlying working mechanisms of the prepared alloy anode.A unique twofold Li electrostripping and plating mechanism under different electrochemical cycling conditions is revealed.Lastly,improved performance of the full cells built with the 3D alloy anode and LiNi_(0.8)Co_(0.1)Mn_(0.1)O_(2)(NCM811)cathode corroborate its potential application capability.Overall,the current work not only showcases the superiority of the 3D alloy as potential anode material for LMBs but also provides fundamental insights into its underlying working mechanisms that may further propel its research and development.
基金supported by the Natural Science Foundation of China(NSFC grant 41272019,41372021)the "973 project" of the Ministry of Science and Technology of China"(2013CB835002, 2013CB837100)+1 种基金the "111 project" of the Programs of Introducing Talents of Discipline to Universities(No: W20136100061)the MOST Special Fund from the State Key Laboratory of Continental Dynamics,Northwest University,China
文摘The early Cambrian pentamerous microfossil Olivooides/Punctatus in South China, which is characterized by a diagnostic stellate tubular apex, has been well-known for its almost complete development sequence that can be confidently traced from embryos and hatched juveniles, to conical adults. However, its zoological affinity remains highly controversial. Here we describe the internal microanatomic structures of the soft-body inside the peridermal theca of Olivooides multisulcatus Qian, 1977, including interradial pairs of tentacles, adradial and perradial frenula, perradial oral marginal lappets and twins of perradial gastric saccule-like humps as well as a circular velarium with striated coronal muscles. Particularly, one specimen shows bifurcated velarial canals along the bell aperture. Both the components of the soft-body and the external theca (or cyst) are arranged in perfect pentaradial symmetry. These characteristics are more compatible with those of living cubomedusans and co-occurring Cambrian athecate embryonic cubozoans. Concerning the presence of peridermal theca, Olivooides most likely represents an extinct thecate stem-group cubomedusae but devoid of both perradial eyes and specialized pedalia. The well-grown soft body inside the peridermal tube displays a set of mixed features of both polyp and medusa.
文摘Lead dissolved in water must be removed in order not to cause diseases, especially from high pH aqueous solution. Various oxides having high specific surface area are often applied to remove lead in water media. To improve removal ability for lead species, it is necessary to understand the adsorbed structure of lead species on oxides. At first, the adsorption behavior of lead from high pH solution in the presence of Ca<sup>2+</sup> and Na+ was compared. Lead and calcium species were adsorbed up to the monolayer, and the adsorption isotherm was analyzed as Langmuir-type adsorption. In the presence of Ca<sup>2+</sup>, the amount of removed lead was reduced. To clarify this influence of Ca<sup>2+</sup>, X-ray absorption spectroscopy was adopted. It was for the first time revealed that lead species at pH > 12 and pH < 10.5 differed, and that lead species adsorbed on various oxides had a similar structure.
基金JSPS KAKENHI Grant Nos.JP17·6708,JP19740332,and JP19K04051 to N.H.and Grant No.JP17K05550 to Y.A.the SPring-8 facility with the approval of the JASRI(Proposal Nos.2005B0272,2005B0307,2006A1077,2006A1307,2006A1792,2007A1277,2007A1286,2008B1247,2009A1444,2018B1144,and 2020A1194).
文摘Synchrotron radiation x-ray diffraction investigations of iron(Fe)and nickel(Ni)are conducted at pressures up to 354 and 368 GPa,respectively,and the equations of state(EOSs)at 298 K for the two elements are obtained for data extending to pressures as high as those at the center of the Earth,using the latest Pt-EOS pressure scale.From a least-squares fit to the Vinet equation using the observed pressure–volume data,the isothermal bulk modulus K0 and its pressure derivative K′0 are estimated to be 159.27(99)GPa and 5.86(4)for hcp-Fe,and 173.5(1.4)GPa and 5.55(5)for Ni.By comparing the present EOSs and extrapolated EOSs reported in the literature for Fe and Ni,the volumes of Fe and Ni at 365 GPa are found to be 2.3%and 1.5%larger than those estimated from extrapolated EOSs in previous studies,respectively.It is concluded that these discrepancies are due to the pressure scale.The present results suggest that the densities of Fe and Ni at a pressure of 365 GPa corresponding to the center of the Earth are 2.3%and 1.5%,respectively,lower than previously thought.
基金Distinguished Young Foundation of Sichuan Province,Grant/Award Number:2020JDJQ0027National Natural Science Foundation of China,Grant/Award Numbers:22108218,20A20145,21878195+2 种基金German Research Foundation,Grant/Award Number:390874152“Young Talent Support Plan”of Xi'an Jiaotong University,Grant/Award Number:HG6J016Qinchuangyuan Innovative Talent Project,Grant/Award Number:QCYRCXM-2022-137。
文摘With exceptional capacity during high-voltage cycling,P3-type Nadeficient layered oxide cathodes have captured substantial attention.Nevertheless,they are plagued by severe capacity degradation over cycling.In this study,tuning and optimizing the phase composition in layered oxides through Li incorporation are proposed to enhance the high-voltage stability.The structural dependence of layered Na_(2/3)LixNi_(0.25)Mn_(0.75)O_(2)þδoxides on the lithium content(0.0≤x≤1.0)offered during synthesis is investigated systematically on an atomic scale.Surprisingly,increasing the Li content triggers the formation of mixed P2/O3-type or P3/P2/O3-type layered phases.As the voltage window is 1.5-4.5 V,P3-type Na2/3Ni_(0.25)Mn_(0.75)O_(2)(NL0.0NMO,R3m)material exhibits a sequence of phase transformations throughout the process of(de)sodiation,that is,O3⇌P3⇌O30⇌O3″.Such complicated phase transitions can be effectively suppressed in the Na2/3Li_(0.7)Ni_(0.25)Mn_(0.75)O_(2.4)(NL_(0.7)NMO)oxide with P2/P3/O3-type mixed phases.Consequently,cathodes made of NL0.7NMO exhibit a substantially enhanced cyclic performance at high voltages compared to that of the P3-type layered NL0.0NMO cathode.Specifically,NL0.7NMO demonstrates an outstanding capacity retention of 98%after 10 cycles at 1 C within 1.5-4.5 V,much higher than that of NL0.0NMO(83%).This work delves into the intricate realm of bolstering the high-voltage durability of layered oxide cathodes,paving the way for advanced sodium-ion battery technologies.
基金The synchrotron radiation measurements were performed at BL20XU at SPring-8,with the approval of the Japan Syn-chrotron Radiation Research Institute(JASRI,proposal numbers 2022B1020,2022A1003,2021B1005,2021B1004,2021A1017,2020A1782).
文摘High-performance all-solid-state lithium-ion batteries require observation,control,and optimization of the electrode structure.X-ray computational tomography(CT)is an effective nondestructive method for observing the electrode structure in three dimensions.However,the limited availability of synchrotron radiation CT,which offers high-resolution imaging with a high signal-to-noise ratio,makes it difficult to conduct experiments and restricts the use of X-ray CT in battery development.Conversely,laboratory CT systems are widely available,but they use X-rays emitted from a metal target,resulting in lower image quality and resolution compared with synchrotron radiation CT.This study explores a method for achieving comparable resolution in laboratory CT images of all-solid-state batteries to that of synchrotron radiation CT.Our method involves using the synchrotron radiation CT images as training data for machine learning super-resolution.The results demonstrate that,by employing an appropriate machine learning algorithm and activation function,along with a sufficiently deep network,the image quality of laboratory CT becomes equivalent to that of synchrotron radiation CT.
基金supported by the research proposal to SPring-8 by Y Kono (No. 2007B1648)the Grant-in-Aid for Scientific Research from the Japanese Government to T Irifune
文摘Simultaneous ultrasonic elastic wave velocity and in situ synchrotron X-ray measurements on grossular garnet were carried out up to 17 GPa and 1 650 K. P- and S-wave vdoeities and bulk and shear modulus showed linear pressure and temperature dependence. These data yielded a pressure derivative of the bulk modulus of 4.42(7) and a shear modulus of 1.27(3), which are in good agreement with those of garnets with variable chemical compositions. Temperature dependence of the bulk modulus of grossular (-1.36×10^-2 GPafK) is also similar to that of other garnets, while the temperature dependence of the shear modulus of grossular (-1.11×10^-2 GPa/K) is higher than those of magnesium end-member garnets and pyrolitic garnet.