Structural Origins of the Enhancement in Ionic Conductivity of a Chalcogenide Compound by Adding AgI. Issue 7 (2nd March 2020)

• Record Type: Journal Article
• Authors: Qiao, Wanchun; Qiao, Ang; Tao, Yunhang; Gu, Shaoxuan; Yue, Yuanzheng; Tao, Haizheng
• Is Part Of: ChemElectroChem. Volume 7:Issue 7(2020)
• Page Start: 1567
• Page End: 1572
• Publication Date: 2020-03-02
• Subjects: solid electrolyte -- ionic conductivity -- EXAFS -- high-energy ball-milling; Electrochemistry -- Periodicals; 541.37
• DOI: 10.1002/celc.201902163
• Languages: English
• ISSNs: 2196-0216

Abstract

Abstract: Through a chemo‐mechanical milling process, we prepared a highly conductive (1.1×10 −3 S ⋅ cm −1 ) amorphous 0.5AgI ⋅ 0.5 Ag3 PS4 conductor, which is much higher than that of pure amorphous Ag3 PS4 (8.5×10 −4 S ⋅ cm −1 ). Detailed structural characterizations indicate that compared to the ionic conductivity of the amorphous Ag3 PS4 conductor, the enhancement can be ascribed to the formation of mixed polymeric anions {[PS4 ]m In } around Ag + ions. Through heat‐treatment at 370 °C for 20 minutes, the room temperature ionic conductivity of the 0.5AgI ⋅ 0.5 Ag3 PS4 conductor is further enhanced by about 4 times. This enhancement can be ascribed to the following two aspects: 1) the existence of residual amorphous phase with higher ionic conductivity; 2) the connection of the fast ionic conductive interfaces between the deposited Ag7 PS6 nano‐crystals and the residual amorphous phase. This work reveals the key roles of both disorder and interface in improving the ionic conductivity of solid‐state electrolytes. Abstract : Mill and heat : A chemo‐mechanical milling process is used to prepare a highly conductive amorphous 0.5AgI ⋅ 0.5 Ag3 PS4 conductor. The mechanisms of the enhancement in ionic conductivity for the present 0.5AgI ⋅ 0.5 Ag3 PS4 amorphous powder together with the heat‐treated one are discussed.