Array of nanosheets render ultrafast and high-capacity Na-ion storage by tunable pseudocapacitance

• Main Authors: Chao, Dongliang, Zhu, Changrong, Yang, Peihua, Xia, Xinhui, Liu, Jilei, Wang, Jin, Fan, Xiaofeng, Savilov, Serguei V., Lin, Jianyi, Fan, Hong Jin, Shen, Ze Xiang
• Other Authors: School of Physical and Mathematical Sciences
• Format: Article
• Language: English
• Published: 2017
• Subjects: Reaction Kinetics and Dynamics; Batteries
• Online Access: https://hdl.handle.net/10356/83885; http://hdl.handle.net/10220/42866
• Institution: Nanyang Technological University

Sodium-ion batteries are a potentially low-cost and safe alternative to the prevailing lithium-ion battery technology. However, it is a great challenge to achieve fast charging and high power density for most sodium-ion electrodes because of the sluggish sodiation kinetics. Here we demonstrate a high-capacity and high-rate sodium-ion anode based on ultrathin layered tin(II) sulfide nanostructures, in which a maximized extrinsic pseudocapacitance contribution is identified and verified by kinetics analysis. The graphene foam supported tin(II) sulfide nanoarray anode delivers a high reversible capacity of ∼1,100 mAh g−1 at 30 mA g−1 and ∼420 mAh g−1 at 30 A g−1, which even outperforms its lithium-ion storage performance. The surface-dominated redox reaction rendered by our tailored ultrathin tin(II) sulfide nanostructures may also work in other layered materials for high-performance sodium-ion storage.