TY - JOUR
T1 - Computational and Experimental Investigations of Na-Ion Conduction in Cubic Na3PSe4
AU - Bo, Shou Hang
AU - Wang, Yan
AU - Kim, Jae Chul
AU - Richards, William Davidson
AU - Ceder, Gerbrand
N1 - Publisher Copyright:
© 2015 American Chemical Society.
PY - 2016/1/12
Y1 - 2016/1/12
N2 - All-solid-state Na-ion batteries that operate at or close to room temperature are a promising next-generation battery technology with enhanced safety and reduced manufacturing cost. An indispensable component of this technology is the solid-state electrolyte that allows rapid shuttling of the mobile cation (i.e., Na+) between the cathode and anode. However, there are very few fast Na-ion conductors with ionic conductivity approaching that of the liquid counterparts (i.e., 1 mS cm-1). In this work, we present the synthesis and characterization of a fast Na-ion conductor, cubic Na3PSe4. This material possesses a room-temperature ionic conductivity exceeding 0.1 mS cm-1 and does not require high-temperature sintering to minimize grain boundary resistance, making it a promising solid-state electrolyte candidate for all-solid-state Na-ion battery applications. On the basis of density functional theory, nudged elastic band, and molecular dynamics investigations, we demonstrate that the framework of cubic Na3PSe4 only permits rapid Na+ diffusion with the presence of defects, and that the formation of the Na vacancy (charge-balanced by slight Se2- oxidation) is more energetically favorable among the various defects considered. This finding provides important guidelines to further improve Na-ion conductivity in this class of materials.
AB - All-solid-state Na-ion batteries that operate at or close to room temperature are a promising next-generation battery technology with enhanced safety and reduced manufacturing cost. An indispensable component of this technology is the solid-state electrolyte that allows rapid shuttling of the mobile cation (i.e., Na+) between the cathode and anode. However, there are very few fast Na-ion conductors with ionic conductivity approaching that of the liquid counterparts (i.e., 1 mS cm-1). In this work, we present the synthesis and characterization of a fast Na-ion conductor, cubic Na3PSe4. This material possesses a room-temperature ionic conductivity exceeding 0.1 mS cm-1 and does not require high-temperature sintering to minimize grain boundary resistance, making it a promising solid-state electrolyte candidate for all-solid-state Na-ion battery applications. On the basis of density functional theory, nudged elastic band, and molecular dynamics investigations, we demonstrate that the framework of cubic Na3PSe4 only permits rapid Na+ diffusion with the presence of defects, and that the formation of the Na vacancy (charge-balanced by slight Se2- oxidation) is more energetically favorable among the various defects considered. This finding provides important guidelines to further improve Na-ion conductivity in this class of materials.
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U2 - 10.1021/acs.chemmater.5b04013
DO - 10.1021/acs.chemmater.5b04013
M3 - Article
AN - SCOPUS:84954425699
SN - 0897-4756
VL - 28
SP - 252
EP - 258
JO - Chemistry of Materials
JF - Chemistry of Materials
IS - 1
ER -