Heteroatom occupancy plays a key role in the precise modulation of specific material regions by introducing foreign elements into the main material matrix,yet it urgently requires further understanding from a spatial ...Heteroatom occupancy plays a key role in the precise modulation of specific material regions by introducing foreign elements into the main material matrix,yet it urgently requires further understanding from a spatial perspective.Herein,we propose a“satellite atom-spinel crystal”concept by synthesizing model catalysts with Fe atoms strategically positioned at two different spatial positions of spinel Co_(3)O_(4)(satellite-Fe at Co_(3)O_(4)(Fe_((Sat))-Co_(3)O_(4))and Fe-doped Co_(3)O_(4)(Co_(3)Fe(In)O_(4))),through which a new catalytic phenomenon is found.Multidimensional in situ spectroscopies revealed that Fe_((Sat))-Co_(3)O_(4) overcomes the crystal field potential energy(FeSat–O>FeSat–O–CoOh)and exhibits 1%(Fe atom)lower impedance than that of Co_(3)Fe(In)O_(4) due to the resistance-free electron delocalization layer formed in Fe_((Sat))-Co_(3)O_(4),which results in tens of times increase of the turnover frequency and mass activity and then a great reduction in the overpotential by 120 mV when used to catalyze the electrochemical oxygen evolution reaction compared to that of Co_(3)Fe(In)O_(4).Density functional theory calculations further dynamically reveal the mechanisms governing electron itinerancy modulation.This study not only provides valuable insights into the impact of heteroatomic spatial positioning on material properties but also significantly expands our understanding of atomic manipulation.展开更多
Fe_(3)GaTe_(2)has attracted significant interest due to its intrinsic room-temperature ferromagnetism,yet its magnetic interactions remain debated.We thoroughly investigate the magnetism of Fe_(3)GaTe_(2)using critica...Fe_(3)GaTe_(2)has attracted significant interest due to its intrinsic room-temperature ferromagnetism,yet its magnetic interactions remain debated.We thoroughly investigate the magnetism of Fe_(3)GaTe_(2)using critical analysis,nitrogen–vacancy(NV)center magnetometry,and Density Function Theory(DFT).Our critical phenomenon analysis with exponents[β=0.3706(9),=1.32(6),σ=4.7(2)]and DFT calculations reveal competition between itinerant and localized spins driven by anisotropic coupling,which can be attributed to a net charge transfer of approximately 0.22 electrons from Fe^(3+)to surrounding Ge/Te atoms.As confirmed by NV center magnetometry,the ferromagnetism in Fe_(3)GaTe_(2)remains robust even in thin-layered sheet of 16 nm(corresponding to approximately 20 layers).The out-of-plane ferromagnetism in thin Fe_(3)GaTe_(2)sheets is stabilized due to the distinct spin interaction energies between intralayers(J_(1)~66.74 meV andJ_(2)~17.33 meV)and interlayers(J_(z)~3.78 meV).In addition,the constant energy contour profiles near the Fermi surface of Fe_(3)GaTe_(2)suggest the presence of both hole and electron pockets with a distorted contour around the K/K′point,indicating hexagonal trigonal warping effects.Furthermore,the layer-resolved electronic band structure uncovers a layer–valley coupling near the Fermi surface,with bands at valleys K and K′associated with different layers.These findings pave way for advanced electronic applications operating above-room-temperature.展开更多
In-situ experimental techniques have been widely applied to uncover the dynamic evolutions of both the structure of catalysts and the interfacial property of catalysis,thus serving as the most important means to gain ...In-situ experimental techniques have been widely applied to uncover the dynamic evolutions of both the structure of catalysts and the interfacial property of catalysis,thus serving as the most important means to gain molecular-level insights into the reaction mechanisms.In this mini review,we summarized recent progress in the applications of the interface-sensitive in-situ Raman and in-situ infrared(IR)spectroscopy towards CO_(2)electroreduction.Specifically,we concentrated on two aspects to clarify the role of both in-situ Raman and in-situ IR in revealing reaction mechanisms of CO_(2)electroreduction.The first one was the in-situ spectroscopy for detecting the active structures.The other one was the in-situ spectroscopy for capturing the reaction intermediates.As powerful guidance for the rational design of catalysts,the reaction mechanism was discussed in the specific examples.Finally,we try to predict the trends for the future development of in-situ spectroscopic techniques towards heterogeneous catalysis.展开更多
Highly hierarchical structures of silver indium tungsten oxide(AgIn(WO_(4))_(2))mesocrystals can be rationally fabricated via the microwave-assisted synthesis method by tuning the initial concentrations of the precurs...Highly hierarchical structures of silver indium tungsten oxide(AgIn(WO_(4))_(2))mesocrystals can be rationally fabricated via the microwave-assisted synthesis method by tuning the initial concentrations of the precursors.Photoluminescence spectra of hierarchical AgIn(WO_(4))_(2) mesocrystals were measured to investigate the correlation between the morphology,pressure,and temperature and their luminescence properties.The materials showed interesting white emission when excited by visible light of wavelength 460 nm.AgIn(WO_(4))_(2) materials having different morphologies displayed notable differences in photogenerated emission performance.The emission was strongly correlated with the surface nanostructures of outgrowths,with larger amounts of outgrowths leading to stronger emission intensities.The pressure-and temperature-dependent photoluminescence properties of these materials have also been investigated under hydrostatic pressures up to 16 GPa at room temperature and in the temperature range from 10 to 300 K.展开更多
In recent years,few-layer or even monolayer ferromagnetic materials have drawn a great deal of attention due to the promising integration of two-dimensional(2D)magnets into next-generation spintronic devices.The SrRuO...In recent years,few-layer or even monolayer ferromagnetic materials have drawn a great deal of attention due to the promising integration of two-dimensional(2D)magnets into next-generation spintronic devices.The SrRuO_(3)monolayer is a rare example of stable 2D magnetism under ambient conditions,but only weak ferromagnetism or antiferromagnetism has been found.The biatomic layer SrRuO_(3)as another environmentally inert 2D magnetic system has been paid less attention heretofore.Here we study both the bi-atomic layer and monolayer SrRuO_(3)in(SrRuO_(3))n/(SrTiO_(3))m(n=1,2)superlattices in which the SrTiO3 serves as a non-magnetic and insulating space layer.Although the monolayer exhibits arguably weak ferromagnetism,we find that the bi-atomic layer exhibits exceedingly strong ferromagnetism with a Tc of 125 K and a saturation magnetization of 1.2μB/Ru,demonstrated by both superconducting quantum interference device(SQUID)magnetometry and element-specific X-ray circular dichroism.Moreover,in the bi-atomic layer SrRuO_(3),we demonstrate that random fluctuations and orbital reconstructions inevitably occurring in the 2D limit are critical to the electrical transport,but are much less critical to the ferromagnetism.Our study demonstrates that the bi-atomic layer SrRuO_(3)is an exceedingly strong 2D ferromagnetic oxide which has great potentials for applications of ultracompact spintronic devices.展开更多
基金supported by the National Natural Science Foundation of China(12405368,12135012)the Natural Science Foundation of Anhui Province(2408085QA016)the Scholarship from the China Scholarship Council(CSC)(202306340088)。
文摘Heteroatom occupancy plays a key role in the precise modulation of specific material regions by introducing foreign elements into the main material matrix,yet it urgently requires further understanding from a spatial perspective.Herein,we propose a“satellite atom-spinel crystal”concept by synthesizing model catalysts with Fe atoms strategically positioned at two different spatial positions of spinel Co_(3)O_(4)(satellite-Fe at Co_(3)O_(4)(Fe_((Sat))-Co_(3)O_(4))and Fe-doped Co_(3)O_(4)(Co_(3)Fe(In)O_(4))),through which a new catalytic phenomenon is found.Multidimensional in situ spectroscopies revealed that Fe_((Sat))-Co_(3)O_(4) overcomes the crystal field potential energy(FeSat–O>FeSat–O–CoOh)and exhibits 1%(Fe atom)lower impedance than that of Co_(3)Fe(In)O_(4) due to the resistance-free electron delocalization layer formed in Fe_((Sat))-Co_(3)O_(4),which results in tens of times increase of the turnover frequency and mass activity and then a great reduction in the overpotential by 120 mV when used to catalyze the electrochemical oxygen evolution reaction compared to that of Co_(3)Fe(In)O_(4).Density functional theory calculations further dynamically reveal the mechanisms governing electron itinerancy modulation.This study not only provides valuable insights into the impact of heteroatomic spatial positioning on material properties but also significantly expands our understanding of atomic manipulation.
基金supported by the National Key R&D Program of China(Grant No.2024YFA1611103)the National Natural Science Foundation of China(Grant Nos.12350410367,12074360,12374128,12074386,12250410238,and 62150410438)+3 种基金the Alliance of International Science Organizations(Grant Nos.ANSO-VF-2022-03 and ANSO-VF-2024-03)Anhui Provincial Major S&T Project(Grant No.s202305a12020005)A portion of this work was supported by the Basic Research Program of the Chinese Academy of Sciences Based on Major Scientific Infrastructures(Grant No.JZHKYPT-2021-08)the High Magnetic Field Laboratory of Anhui Province under Contract No.AHHM-FX-2020-02.
文摘Fe_(3)GaTe_(2)has attracted significant interest due to its intrinsic room-temperature ferromagnetism,yet its magnetic interactions remain debated.We thoroughly investigate the magnetism of Fe_(3)GaTe_(2)using critical analysis,nitrogen–vacancy(NV)center magnetometry,and Density Function Theory(DFT).Our critical phenomenon analysis with exponents[β=0.3706(9),=1.32(6),σ=4.7(2)]and DFT calculations reveal competition between itinerant and localized spins driven by anisotropic coupling,which can be attributed to a net charge transfer of approximately 0.22 electrons from Fe^(3+)to surrounding Ge/Te atoms.As confirmed by NV center magnetometry,the ferromagnetism in Fe_(3)GaTe_(2)remains robust even in thin-layered sheet of 16 nm(corresponding to approximately 20 layers).The out-of-plane ferromagnetism in thin Fe_(3)GaTe_(2)sheets is stabilized due to the distinct spin interaction energies between intralayers(J_(1)~66.74 meV andJ_(2)~17.33 meV)and interlayers(J_(z)~3.78 meV).In addition,the constant energy contour profiles near the Fermi surface of Fe_(3)GaTe_(2)suggest the presence of both hole and electron pockets with a distorted contour around the K/K′point,indicating hexagonal trigonal warping effects.Furthermore,the layer-resolved electronic band structure uncovers a layer–valley coupling near the Fermi surface,with bands at valleys K and K′associated with different layers.These findings pave way for advanced electronic applications operating above-room-temperature.
基金supported by the National Natural Science Foundation of China(22322901 and 22209163)the Strategic Priority Research Program of the Chinese Academy of Sciences(XDB0450401)+2 种基金the CAS Project for Young Scientists in Basic Research(YSBR-022)the National Key Research and Development Program of China(2022YFC2106000)the USTC Research Funds of the Double First-Class Initiative。
文摘In-situ experimental techniques have been widely applied to uncover the dynamic evolutions of both the structure of catalysts and the interfacial property of catalysis,thus serving as the most important means to gain molecular-level insights into the reaction mechanisms.In this mini review,we summarized recent progress in the applications of the interface-sensitive in-situ Raman and in-situ infrared(IR)spectroscopy towards CO_(2)electroreduction.Specifically,we concentrated on two aspects to clarify the role of both in-situ Raman and in-situ IR in revealing reaction mechanisms of CO_(2)electroreduction.The first one was the in-situ spectroscopy for detecting the active structures.The other one was the in-situ spectroscopy for capturing the reaction intermediates.As powerful guidance for the rational design of catalysts,the reaction mechanism was discussed in the specific examples.Finally,we try to predict the trends for the future development of in-situ spectroscopic techniques towards heterogeneous catalysis.
基金financially supported by the National Key R&D Program on Nano Science & Technology of the MOST (2017YFA0207301)the National Natural Science Foundation of China (21925110,21890751,91745113,12147105,22275205,and 22005284)+9 种基金the National Program for Support of Top-notch Young Professionals,the Fundamental Research Funds for the Central Universities (WK2060190084)the Youth Innovation Promotion Association CAS (2018500),the National Postdoctoral Program for Innovative Talents (BX20190307,BX20190308)the Major Program of Development Foundation of Hefei Centre for Physical Science and Technology (2016FXZY001)the Users with Excellence Project of Hefei Science Centre CAS (2018HSC-UE002)the CAS Project for Young Scientists in Basic Research (YSBR-070)the support from the beamline 1W1B of Beijing Synchrotron Radiation Facility (BSRF,Beijing,China)beamline BL12B-a of the National Synchrotron Radiation Laboratory (NSRL,Hefei,China)the Cryo-EM Centre at the University of Science and Technology of China for the EM facility supportpartially carried out at the USTC Centre for Micro and Nanoscale Research and Fabricationthe support from the Super Computer Centre of USTCSCC and SCCAS
基金S.H.Y.acknowledges the special funding support from the National Basic Research Program of China(No.2010CB934700)the National Natural Science Foundation of China(NSFC,No.50732006)+1 种基金the Program of International S&T Cooperation(No.2010DFA41170)and the Principal Investigator Award by the National Synchrotron Radiation Laboratory at the University of Science and Technology of China.
文摘Highly hierarchical structures of silver indium tungsten oxide(AgIn(WO_(4))_(2))mesocrystals can be rationally fabricated via the microwave-assisted synthesis method by tuning the initial concentrations of the precursors.Photoluminescence spectra of hierarchical AgIn(WO_(4))_(2) mesocrystals were measured to investigate the correlation between the morphology,pressure,and temperature and their luminescence properties.The materials showed interesting white emission when excited by visible light of wavelength 460 nm.AgIn(WO_(4))_(2) materials having different morphologies displayed notable differences in photogenerated emission performance.The emission was strongly correlated with the surface nanostructures of outgrowths,with larger amounts of outgrowths leading to stronger emission intensities.The pressure-and temperature-dependent photoluminescence properties of these materials have also been investigated under hydrostatic pressures up to 16 GPa at room temperature and in the temperature range from 10 to 300 K.
基金the National Natural Science Foundation of China(Nos.52072244 and 12104305)the Science and Technology Commission of Shanghai Municipality(No.21JC1405000)+1 种基金the ShanghaiTech Startup Fund.This research used resources of the Advanced Photon Source,a U.S.Department of Energy(DOE)Office of Science User Facility operated for the DOE Office of Science by Argonne National Laboratory under Contract(No.DE-AC02-06CH11357)the Advanced Light Source,a U.S.DOE Office of Science User Facility under Contract(No.DE-AC02-05CH11231).
文摘In recent years,few-layer or even monolayer ferromagnetic materials have drawn a great deal of attention due to the promising integration of two-dimensional(2D)magnets into next-generation spintronic devices.The SrRuO_(3)monolayer is a rare example of stable 2D magnetism under ambient conditions,but only weak ferromagnetism or antiferromagnetism has been found.The biatomic layer SrRuO_(3)as another environmentally inert 2D magnetic system has been paid less attention heretofore.Here we study both the bi-atomic layer and monolayer SrRuO_(3)in(SrRuO_(3))n/(SrTiO_(3))m(n=1,2)superlattices in which the SrTiO3 serves as a non-magnetic and insulating space layer.Although the monolayer exhibits arguably weak ferromagnetism,we find that the bi-atomic layer exhibits exceedingly strong ferromagnetism with a Tc of 125 K and a saturation magnetization of 1.2μB/Ru,demonstrated by both superconducting quantum interference device(SQUID)magnetometry and element-specific X-ray circular dichroism.Moreover,in the bi-atomic layer SrRuO_(3),we demonstrate that random fluctuations and orbital reconstructions inevitably occurring in the 2D limit are critical to the electrical transport,but are much less critical to the ferromagnetism.Our study demonstrates that the bi-atomic layer SrRuO_(3)is an exceedingly strong 2D ferromagnetic oxide which has great potentials for applications of ultracompact spintronic devices.
