Achieving high-capacity and long-life K+ storage enabled by constructing yolk-shell Sb2S3@N, S-doped carbon nanorod anodes

• Published in: Journal of energy chemistry 2023-01, Vol.76, p.547-556
• Main Authors: Xiao, Bensheng, Zhang, Hehe, Sun, Zhefei, Li, Miao, Fan, Yingzhu, Lin, Haichen, Liu, Haodong, Jiang, Bing, Shen, Yanbin, Wang, Ming-Sheng, Li, Meicheng, Zhang, Qiaobao
• Format: Article
• Language: English
• Subjects: Antimony sulfide; In situ TEM; Potassium-ion batteries; Super-stable cyclability; Yolk-shell structure
• ISSN: 2095-4956
• DOI: 10.1016/j.jechem.2022.09.050

A in situ transmission electron microscopy study of an anode consisting of yolk-shell structured Sb2S3 confined in N, S co-doped hollow carbon nanorod clearly demonstrates that the buffer space between the Sb2S3 core and N, S co-doped carbon shell can effectively accommodate the large expansion of active Sb2S3 during potassiation, thus ensuring the high-capacity and long-cycle stability. [Display omitted] As promising anode candidates for potassium-ion batteries (PIBs), antimony sulfide (Sb2S3) possesses high specific capacity but suffers from massive volume expansion and sluggish kinetics due to the large K+ insertion, resulting in inferior cycling and rate performance. To address these challenges, a yolk-shell structured Sb2S3 confined in N, S co-doped hollow carbon nanorod (YS-Sb2S3@NSC) working as a viable anode for PIBs is proposed. As directly verified by in situ transmission electron microscopy (TEM), the buffer space between the Sb2S3 core and thin carbon shell can effectively accommodate the large expansion stress of Sb2S3 without cracking the shell and the carbon shell can accelerate electron transport and K+ diffusion, which plays a significant role in reinforcing the structural stability and facilitating charge transfer. As a result, the YS-Sb2S3@NSC electrode delivers a high reversible K+ storage capacity of 594.58 mA h g−1 at 0.1 A g−1 and a long cycle life with a slight capacity degradation (0.01% per cycle) for 2000 cycles at 1 A g−1 while maintaining outstanding rate capability. Importantly, utilizing in in situ/ex situ microscopic and spectroscopic characterizations, the origins of performance enhancement and K+ storage mechanism of Sb2S3 were clearly elucidated. This work provides valuable insights into the rational design of high-performance and durable transition metal sulfides-based anodes for PIBs.