In recent years,sodium-ion batteries(SIBs)have been considered as one of the most promising alternatives to lithium-ion batteries(LIBs).Here,a new Na-super-ionic conductor(NASICON)cathode material Na Fe_(2)PO_(4)(SO_(...In recent years,sodium-ion batteries(SIBs)have been considered as one of the most promising alternatives to lithium-ion batteries(LIBs).Here,a new Na-super-ionic conductor(NASICON)cathode material Na Fe_(2)PO_(4)(SO_(4))_(2)is successfully prepared through solid state method for SIBs.While the poor electronic conductivity of iron-based materials results in its poor rate and cycle performance.Then the electrochemical is effectively promoting via Ca^(2+)doping.Na_(0.84)Ca_(0.08)Fe_(2)PO_(4)(SO_(4))_(2)have achieved considerable electrochemical properties.The first discharge specific capacity is 121.6 m A h g^(-1)at 25 m A g^(-1)with the voltage platform(-3.1 V)corresponding to Fe^(2+/3+).After 100 cycles,the capacity retention is 55.1%.The excellent electrochemical performance is caused by some Na^(+)is substituted by Ca^(2+)and leading to the fast sodium kinetics,which is well proved by the powder X-ray diffraction pattern and well corresponding to the galvanostatic intermittent titration technique and cyclic voltammetry testing result(the diffusivity values are around at 10^(-12)cm^(2)s^(-1)).展开更多
基金the National Natural Science Foundation of China(No.91963118)the Science Technology Program of Jilin Province(No.20200201066JC)+1 种基金the“13th Five-Year”Science and Technology Research from the Education Department of Jilin Province(No.JJKH20201179KJ)the 111 Project(No.B13013)。
文摘In recent years,sodium-ion batteries(SIBs)have been considered as one of the most promising alternatives to lithium-ion batteries(LIBs).Here,a new Na-super-ionic conductor(NASICON)cathode material Na Fe_(2)PO_(4)(SO_(4))_(2)is successfully prepared through solid state method for SIBs.While the poor electronic conductivity of iron-based materials results in its poor rate and cycle performance.Then the electrochemical is effectively promoting via Ca^(2+)doping.Na_(0.84)Ca_(0.08)Fe_(2)PO_(4)(SO_(4))_(2)have achieved considerable electrochemical properties.The first discharge specific capacity is 121.6 m A h g^(-1)at 25 m A g^(-1)with the voltage platform(-3.1 V)corresponding to Fe^(2+/3+).After 100 cycles,the capacity retention is 55.1%.The excellent electrochemical performance is caused by some Na^(+)is substituted by Ca^(2+)and leading to the fast sodium kinetics,which is well proved by the powder X-ray diffraction pattern and well corresponding to the galvanostatic intermittent titration technique and cyclic voltammetry testing result(the diffusivity values are around at 10^(-12)cm^(2)s^(-1)).
