TY  - JOUR
AU  - Liu, Yujian
AU  - Liu, Limin
AU  - Peng, Jinsong
AU  - Zhou, Xiaoliang
AU  - Liang, Dongshi
AU  - Zhao, Lei
AU  - Su, Jiawen
AU  - Zhang, Bo
AU  - Li, Si
AU  - Zhang, Naiqing
AU  - Ma, Qianli
AU  - Tietz, Frank
TI  - A niobium-substituted sodium superionic conductor with conductivity higher than 5.5 mS cm−1 prepared by solution-assisted solid-state reaction method
JO  - Journal of power sources
VL  - 518
SN  - 0378-7753
CY  - New York, NY [u.a.]
PB  - Elsevier
M1  - FZJ-2021-04267
SP  - 230765 -
PY  - 2022
AB  - Although research on all-solid-state sodium batteries (ASSSBs) have been conducted for many years, the solidstateelectrolyte (SSE) material is still far from practical application at room temperature. One major reason isthat no suitable electrolyte material with high ionic conductivity has been found yet. In this study, Nb5+ isintroduced into NASICON-type solid electrolyte, where Nb5+ substituted Na3.4Zr2Si2.4P0.6O12 (NZSP) is preparedby a solution-assisted solid-state reaction method. The best ionic conductivity is as high as 5.51 mS cm􀀀 1 which isa significant improvement. High-frequency electrochemical impedance spectroscopy shows that the increase intotal conductivity is mainly due to the decrease of grain boundary impedance as well as bulk impedance. Thedecrease in grain boundary impedance is probably owing to the increase in density of the electrolyte materialafter incorporation of the Nb content, which has a beneficial impact of the sintering of NZSP. The decrease inbulk impedance rather results from the ratio of sodium ion concentration and sodium vacancy concentration of3.3:0.7 in the crystal structure, thus facilitating the sodium ion transport. Symmetric cells with sodium metal aselectrodes (Na|Nb5+ substituted NZSP|Na) are subsequently assembled and cycled stably for 60 cycles at acurrent density of 0.05 mA/cm2.
LB  - PUB:(DE-HGF)16
UR  - <Go to ISI:>//WOS:000720745000001
DO  - DOI:10.1016/j.jpowsour.2021.230765
UR  - https://juser.fz-juelich.de/record/902445
ER  -