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Title: Structure‐mechanical properties correlation in bulk LiPON glass produced by nitridation of metaphosphate melts
Abstract The glassy solid electrolyte Lithium phosphorous oxynitride (LiPON) has been widely researched in thin film solid state battery format due to its outstanding stability when cycled against lithium. In addition, recent reports show thin film LiPON having interesting mechanical behaviors, especially its ability to resist micro‐scale cracking via densification and shear flow. In the present study, we have produced bulk LiPON glasses with varying nitrogen contents by ammonolysis of LiPO3melts. The resulting compositions were determined to be LiPO3‐3z/2Nz, where 0 ≤ z ≤ 0.75, and the z value of 0.75 is among the highest ever reported for this series of LiPON glasses. The short‐range order structures of the different resulting compositions were characterized by infrared, Raman,31P magic angle spinning nuclear magnetic resonance, and X‐ray photoelectron spectroscopies. Instrumented nano‐indentation was used to measure mechanical properties. It was observed that similar to previous studies, both trigonally coordinated (Nt) and doubly bonded (Nd) N co‐exist in the glasses in about the same amounts forz ≤ 0.36, the limit of N content in most previous studies. For glasses withz > 0.36, it was found that the fraction of the Ntincreased significantly while the fraction of Ndcorrespondingly decreased. The incorporation of nitrogen increased both the elastic modulus and hardness of the glass by approximately a factor of 1.5 when N/P ratio reaches 0.75. At the same time, an apparent embrittlement of the glass was observed due to nitridation, which was revealed by nanoindentation with an extra sharp nanoindenter tip.  more » « less
Award ID(s):
1936913
PAR ID:
10480287
Author(s) / Creator(s):
; ; ; ;
Publisher / Repository:
American Ceramic Society
Date Published:
Journal Name:
Journal of the American Ceramic Society
Volume:
106
Issue:
11
ISSN:
0002-7820
Page Range / eLocation ID:
6565 to 6576
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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