In situ formed robust submicron-sized nanocrystalline aggregates enable highly-reversible potassium ion storage. (October 2021)

• Record Type: Journal Article
• Authors: Chen, Kuan-Ting; Yang, Yi-Chun; Lyu, Lian-Ming; Lu, Ming-Yen; Tuan, Hsing-Yu
• Is Part Of: Nano energy. Volume 88(2021)
• Publication Date: 2021-10
• Subjects: Potassium-ion batteries -- Anode -- Nanocrystalline -- Bismuth -- Antimony -- Ball milling; Nanoscience -- Periodicals; Nanotechnology -- Periodicals; Nanostructured materials -- Periodicals; Power resources -- Technological innovations -- Periodicals; Nanoscience; Nanostructured materials; Nanotechnology; Power resources -- Technological innovations; Periodicals; 621.042
• DOI: 10.1016/j.nanoen.2021.106233
• Languages: English
• ISSNs: 2211-2855

Abstract

Abstract: We report an electrode architecture made of submicron-sized nanocrystalline aggregates obtained in situ from ball-milled BiSb crystals during the potassiation/depotassiation process for use as a potassium ion battery electrode with high electrochemical performance and great stability. Nanocrystalline aggregates are individual particles composed of nanocrystals clustered together. The interconnected nanoparticle network as a potassium ion battery (PIB) electrode shows various advantageous characteristics, including adaption to related structures variation, stable SEI layer formation between the interface of electrode and electrolyte, and high efficiency in conductivity and ion migration/diffusion. As the anode of a PIB, the BiSb nanocrystalline aggregate achieves a high capacity of 514.1 mA h g −1 after 100 cycles at 0.25 A g −1, a high-rate capability of up to 10 A g −1, and an ultra-stable life cycle for 6000 cycles. A series of analyses including consecutive in situ X-ray diffraction measurements, in situ electrochemical impedance spectroscopy, and ex situ electron microscopy, are conducted to demonstrate the relevant reaction mechanism of the nanocrystalline aggregates during the evolution of composition as well as their structure during the cycling process. Graphical Abstract: BiSb submicron-sized nanocrystalline aggregates obtained in situ from ball-milled crystals during the cycling process enable great stability for potassium ion storage. Consecutive in situ X-ray diffraction measurements, in situ electrochemical impedance spectroscopy, and ex situ electron microscopy were carried out to reveal the relevant reaction mechanism. ga1 Highlights: A potassium ion anode with the architecture made of submicron-sizednanocrystalline aggregates was obtained in situ from ball-milled BiSb. BiSb nanocrystalline aggregates deliver a capacity of 514.1 mA h g -1, a rate capability up to 10 A g -1, and a cycle life for 6000 cycles. Consecutive in situ X-ray diffraction, in situ EIS, and ex situ TEM were presented to reveal the relevant reactionmechanism. The interconnectednanoparticle network achieves high-efficiency in conductivity and ion migrationand diffusion.