In Situ Formation of Hierarchical Bismuth Nanodots/Graphene Nanoarchitectures for Ultrahigh‐Rate and Durable Potassium‐Ion Storage. Issue 2 (11th December 2019)

• Record Type: Journal Article
• Authors: Zhao, Yuanxin; Ren, Xiaochuan; Xing, Zhenjiang; Zhu, Daming; Tian, Weifeng; Guan, Cairu; Yang, Yong; Qin, Wenming; Wang, Juan; Zhang, Lili; Huang, Yaobo; Wen, Wen; Li, Xiaolong; Tai, Renzhong
• Is Part Of: Small. Volume 16:Issue 2(2020)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2019-12-11
• Subjects: alloy anode -- bismuth nanodots -- operando X‐ray diffraction -- potassium‐ion battery -- 2D sodium bismuthate; Nanotechnology -- Periodicals; Nanoparticles -- Periodicals; Microtechnology -- Periodicals; 620.5
• DOI: 10.1002/smll.201905789
• Languages: English
• ISSNs: 1613-6810

Abstract

Abstract: Metallic bismuth (Bi) has been widely explored as remarkable anode material in alkali‐ion batteries due to its high gravimetric/volumetric capacity. However, the huge volume expansion up to ≈406% from Bi to full potassiation phase K3 Bi, inducing the slow kinetics and poor cycling stability, hinders its implementation in potassium‐ion batteries (PIBs). Here, facile strategy is developed to synthesize hierarchical bismuth nanodots/graphene (BiND/G) composites with ultrahigh‐rate and durable potassium ion storage derived from an in situ spontaneous reduction of sodium bismuthate/graphene composites. The in situ formed ultrafine BiND (≈3 nm) confined in graphene layers can not only effectively accommodate the volume change during the alloying/dealloying process but can also provide high‐speed channels for ionic transport to the highly active BiND. The BiND/G electrode provides a superior rate capability of 200 mA h g −1 at 10 A g −1 and an impressive reversible capacity of 213 mA h g −1 at 5 A g −1 after 500 cycles with almost no capacity decay. An operando synchrotron radiation‐based X‐ray diffraction reveals distinctively sharp multiphase transitions, suggesting its underlying operation mechanisms and superiority in potassium ion storage application. Abstract : A hierarchical bismuth nanodots/graphene nanoarchitecture is designed and fabricated through simple in situ formation as a superior anode material for potassium‐ion batteries. The distinctively underlying operation mechanisms are revealed by operando X‐ray diffraction experiments, and the bismuth alloy anode exhibits state‐of‐the‐art rate performance and unprecedented capacity retention.