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Title: Unlocking High Capacity and Fast Na + Diffusion of H x CrS 2 by Proton‐Exchange Pretreatment
Abstract

This study presents a new material, “HxCrS2” (denotes approximate composition) formed by proton‐exchange of NaCrS2which has a measured capacity of 728 mAh g−1with significant improvements to capacity retention, sustaining over 700 mAh g−1during cycling experiments. This is the highest reported capacity for a transition metal sulfide electrode and outperforms the most promising proposed sodium anodes to date. HxCrS2exhibits a biphasic structure featuring alternating crystalline and amorphous lamella on the scale of a few nanometers. This unique structural motif enables reversible access to Cr redox in the material resulting in higher capacities than seen in the parent structure which features only S redox. Pretreatment by proton‐exchange offers a route to materials such as HxCrS2which provide fast diffusion and high capacities for sodium‐ion batteries.

 
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Award ID(s):
2011750
NSF-PAR ID:
10391426
Author(s) / Creator(s):
 ;  ;  ;  ;  ;  
Publisher / Repository:
Wiley Blackwell (John Wiley & Sons)
Date Published:
Journal Name:
Advanced Materials
Volume:
35
Issue:
10
ISSN:
0935-9648
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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