Journal Article

FZJ-2018-04619

http://join2-wiki.gsi.de/foswiki/pub/Main/Artwork/join2_logo100x88.png Arrhenius Behavior of the Bulk Na-Ion Conductivity in Na 3 Sc 2 (PO 4 ) 3 Single Crystals Observed by Microcontact Impedance Spectroscopy

Rettenwander, D. (Corresponding author) ; Redhammer, G. J. ; Guin, M. ; Benisek, A. ; Krüger, H. ; Guillon, O.FZJ* ; Wilkening, M. ; Tietz, F.FZJ* ; Fleig, J.

2018
American Chemical Society Washington, DC

This record in other databases:      

Please use a persistent id in citations: http://hdl.handle.net/2128/20214  doi:10.1021/acs.chemmater.8b00179

Abstract: NASICON-based solid electrolytes with exceptionally high Na-ion conductivities are considered to enable future all solid-state Na-ion battery technologies. Despite 40 years of research the interrelation between crystal structure and Na-ion conduction is still controversially discussed and far from being fully understood. In this study, microcontact impedance spectroscopy combined with single crystal X-ray diffraction, and differential scanning calorimetry is applied to tackle the question how bulk Na-ion conductivity σbulk of sub-mm-sized flux grown Na3Sc2(PO4)3 (NSP) single crystals is influenced by supposed phase changes (α, β, and γ phase) discussed in literature. Although we found a smooth structural change at around 140 °C, which we assign to the β → γ phase transition, our conductivity data follow a single Arrhenius law from room temperature (RT) up to 220 °C. Obviously, the structural change, being mainly related to decreasing Na-ion ordering with increasing temperature, does not cause any jumps in Na-ion conductivity or any discontinuities in activation energies Ea. Bulk ion dynamics in NSP have so far rarely been documented; here, under ambient conditions, σbulk turned out to be as high as 3 × 10–4 S cm–1 at RT (Ea, bulk = 0.39 eV) when directly measured with microcontacts for individual small single crystals.

---

Contributing Institute(s):

1. Werkstoffsynthese und Herstellungsverfahren (IEK-1)
2. Helmholtz-Institut Münster Ionenleiter für Energiespeicher (IEK-12)

Research Program(s):

1. 131 - Electrochemical Storage (POF3-131) (POF3-131)

Appears in the scientific report 2018

---

Database coverage:
; ; Current Contents - Engineering, Computing and Technology ; Current Contents - Physical, Chemical and Earth Sciences ; Ebsco Academic Search ; Free to read ; IF >= 5 ; JCR ; Nationallizenz ; SCOPUS ; Science Citation Index ; Science Citation Index Expanded ; Thomson Reuters Master Journal List ; Web of Science Core Collection

---