Iron-based superconductor family FeX(X=S,Se,Te)has been one of the research foci in physics and material science due to their record-breaking superconducting temperature(FeSe film)and rich physical phenomena.Recently,...Iron-based superconductor family FeX(X=S,Se,Te)has been one of the research foci in physics and material science due to their record-breaking superconducting temperature(FeSe film)and rich physical phenomena.Recently,FeS,the least studied Fe X compound(due to the difficulty in synthesizing high quality macroscopic crystals)attracted much attention because of its puzzling superconducting pairing symmetry.In this work,combining scanning tunneling microscopy and angle resolved photoemission spectroscopy(ARPES)with sub-micron spatial resolution,we investigate the intrinsic electronic structures of superconducting FeS from individual single crystalline domains.Unlike FeTe or FeSe,FeS remains identical tetragonal structure from room temperature down to 5 K,and the band structures observed can be well reproduced by our ab-initio calculations.Remarkably,mixed with the 1×1 tetragonal metallic phase,we also observe the coexistence of √5×√5 reconstructed insulating phase in the crystal,which not only helps explain the unusual properties of FeS,but also demonstrates the importance of using spatially resolved experimental tools in the study of this compound.展开更多
Garnet-type Li_7La_(3)Zr_(2)O_(12)(LLZO) has high ionic conductivity and good compatibility with lithium metal.High-temperature processing has been proven an effective method to decrease the interface resistance of ca...Garnet-type Li_7La_(3)Zr_(2)O_(12)(LLZO) has high ionic conductivity and good compatibility with lithium metal.High-temperature processing has been proven an effective method to decrease the interface resistance of cathodeILLZO.However,its application is still hindered by the interlayer co-diffusion with the cathode and high sintering temperature(>1200℃).In this work,a new garnet-type composite solid-state electrolyte(SSE) Li_(6.54)La_(2.96)Ba_(0.04)Zr_(1.5)Nb_(0.5)O_(12)-LiCoO_(2)(LLBZNO-LCO) is firstly proposed to improve the chemical stability and electrochemical properties of garnet with high-temperature processing.Small doses of LCO(3%) can significantly decrease the LCOISSE interface resistance from 121.2 to 10.1 Ω cm~2,while the sintering temperature of garnet-type LLBZNO decreases from 1230 to 1000℃.The all-solid-state battery based on the sintered LLBZNO-LCO SSE exhibits excellent cycling stability.Our approach achieves an enhanced LCOISSE interface and an improved sintering activity of garnet SSE,which provides a new strategy for optimizing the comprehensive performance of garnet SSE.展开更多
基金Project supported by CAS-Shanghai Science Research Center,China(Grant No.CAS-SSRC-YH-2015-01)the National Key R&D Program of China(Grant No.2017YFA0305400)+4 种基金the National Natural Science Foundation of China(Grant Nos.11674229,11227902,and 11604207)the EPSRC Platform Grant(Grant No.EP/M020517/1)Hefei Science Center,Chinese Academy of Sciences(Grant No.2015HSC-UE013)Science and Technology Commission of Shanghai Municipality,China(Grant No.14520722100)the Strategic Priority Research Program(B)of the Chinese Academy of Sciences(Grant No.XDB04040200)。
文摘Iron-based superconductor family FeX(X=S,Se,Te)has been one of the research foci in physics and material science due to their record-breaking superconducting temperature(FeSe film)and rich physical phenomena.Recently,FeS,the least studied Fe X compound(due to the difficulty in synthesizing high quality macroscopic crystals)attracted much attention because of its puzzling superconducting pairing symmetry.In this work,combining scanning tunneling microscopy and angle resolved photoemission spectroscopy(ARPES)with sub-micron spatial resolution,we investigate the intrinsic electronic structures of superconducting FeS from individual single crystalline domains.Unlike FeTe or FeSe,FeS remains identical tetragonal structure from room temperature down to 5 K,and the band structures observed can be well reproduced by our ab-initio calculations.Remarkably,mixed with the 1×1 tetragonal metallic phase,we also observe the coexistence of √5×√5 reconstructed insulating phase in the crystal,which not only helps explain the unusual properties of FeS,but also demonstrates the importance of using spatially resolved experimental tools in the study of this compound.
基金financially supported by the National Natural Science Foundation of China (52102323, 51972298)the China Postdoctoral Science Foundation (2021M703055)+1 种基金the National Key R&D Program of China (2021YFB4001401)the Key Research Program of the Chinese Academy of Sciences (ZDRWCN-2021-3-1)。
文摘Garnet-type Li_7La_(3)Zr_(2)O_(12)(LLZO) has high ionic conductivity and good compatibility with lithium metal.High-temperature processing has been proven an effective method to decrease the interface resistance of cathodeILLZO.However,its application is still hindered by the interlayer co-diffusion with the cathode and high sintering temperature(>1200℃).In this work,a new garnet-type composite solid-state electrolyte(SSE) Li_(6.54)La_(2.96)Ba_(0.04)Zr_(1.5)Nb_(0.5)O_(12)-LiCoO_(2)(LLBZNO-LCO) is firstly proposed to improve the chemical stability and electrochemical properties of garnet with high-temperature processing.Small doses of LCO(3%) can significantly decrease the LCOISSE interface resistance from 121.2 to 10.1 Ω cm~2,while the sintering temperature of garnet-type LLBZNO decreases from 1230 to 1000℃.The all-solid-state battery based on the sintered LLBZNO-LCO SSE exhibits excellent cycling stability.Our approach achieves an enhanced LCOISSE interface and an improved sintering activity of garnet SSE,which provides a new strategy for optimizing the comprehensive performance of garnet SSE.
