Exceptionally High Ionic Conductivity in Na<sub>3</sub> P<sub>0.62</sub> As<sub>0.38</sub> S<sub>4</sub> with Improved Moisture Stability for Solid-State Sodium-Ion Batteries.

Yu, Zhaoxin; Shang, Shun-Li; Seo, Joo-Hwan; Wang, Daiwei; Luo, Xiangyi; Huang, Qingquan; Chen, Shuru; Lu, Jun et al. · Adv Mater · 2017

basic_science · Level V

Where this comes from

Abstract

A Na-ion solid-state electrolyte, Na<sub>3</sub> P<sub>0.62</sub> As<sub>0.38</sub> S<sub>4</sub> , is developed with an exceptionally high conductivity of 1.46 mS cm<sup>-1</sup> at 25 °C and enhanced moisture stability. Dual effects of alloying element As (lattice expansion and a weaker AsS bond strength) are responsible for the superior conductivity. Improved moisture stability is regulated by shifting low-energy moisture reactions to high-energy ones due to As.