Nb-based tungsten bronze oxides have emerged as attractive materials in various fields,owing to the structural openings and simple synthesis method.In this work,the tetragonal tungsten bronze(TTB)NaWNbO_(6) was prepar...Nb-based tungsten bronze oxides have emerged as attractive materials in various fields,owing to the structural openings and simple synthesis method.In this work,the tetragonal tungsten bronze(TTB)NaWNbO_(6) was prepared by solid state reaction at a relatively low temperature of 775°C.The local structure was systematically studied by solid state nuclear magnetic resonance(SSNMR)with the aid of transition electronic microscopy(TEM).The analysis indicates that NaWNbO6 has pentagonal,square,and triangular tunnels.Notably,square tunnels were partly occupied(50%)by Na,which creates the ability for the Li-ion storage with a volumetric capacity of 210 A·h·L^(−1)at 0.2 C.The 2D ^(23)Na-^(23)Na EXSY results further suggest the ability of ions to fast exchange between the tetragonal and pentagonal tunnels,resulting in a high-rate performance 20 C.展开更多
基金supported by the National Natural Science Foundation of China(Nos.22090043,21622101)the Guangxi Natural Science Foundation,China(No.2019GXNSFGA245006).
文摘Nb-based tungsten bronze oxides have emerged as attractive materials in various fields,owing to the structural openings and simple synthesis method.In this work,the tetragonal tungsten bronze(TTB)NaWNbO_(6) was prepared by solid state reaction at a relatively low temperature of 775°C.The local structure was systematically studied by solid state nuclear magnetic resonance(SSNMR)with the aid of transition electronic microscopy(TEM).The analysis indicates that NaWNbO6 has pentagonal,square,and triangular tunnels.Notably,square tunnels were partly occupied(50%)by Na,which creates the ability for the Li-ion storage with a volumetric capacity of 210 A·h·L^(−1)at 0.2 C.The 2D ^(23)Na-^(23)Na EXSY results further suggest the ability of ions to fast exchange between the tetragonal and pentagonal tunnels,resulting in a high-rate performance 20 C.
