Alloyed Cu/Si core-shell nanoflowers on the three-dimensional graphene foam as an anode for lithium-ion batteries. (20th May 2019)

• Record Type: Journal Article
• Authors: Liu, Chenguang; Zhao, Yinchao; Yi, Ruowei; Sun, Yi; Li, Yinqing; Yang, Li; Mitrovic, Ivona; Taylor, Stephen; Chalker, Paul; Zhao, Cezhou
• Is Part Of: Electrochimica acta. Volume 306(2019)
• Page Start: 45
• Page End: 53
• Publication Date: 2019-05-20
• Subjects: Silicon-based lithium-ion batteries -- Three-dimensional graphene foam -- Alloyed Cu/Si nanoflowers -- Core-shell structure; Electrochemistry -- Periodicals; Electrochemistry, Industrial -- Periodicals; 541.37
• DOI: 10.1016/j.electacta.2019.03.071
• Languages: English
• ISSNs: 0013-4686

Abstract

Abstract: In this study, we demonstrate a facile method to fabricate a flexible alloyed copper/silicon core-shell nanoflowers structure anchored on the three-dimensional graphene foam as a current collector. This combination provides flexible and free-standing structure and three-dimensional conductive network, allowing unique properties for current collection and transmission. The copper oxide nanoflowers are synthesized on the three-dimensional graphene foam by a simple electrodeposition and etching, which serves as an outstanding template to retard the stress effects during the lithiation/delithiation of silicon. After the silicon coating uniformly deposited on the copper oxide nanoflowers, a simple hydrogen annealing was applied to reduce copper oxide nanoflowers and form the copper/silicon alloy, remarkably enhancing the conductivity of silicon. Moreover, this structure can be directly assembled without any conductive additive or binder. In electrochemical testing, the resulting copper/silicon core-shell nanoflowered electrode demonstrates a high initial capacity of 1869 mAh g −1 at 1.6 A g −1, with a high retention rate of 66.6% after 500 cycles. More importantly, at a high current density of 10 A g −1, this anode still remains a high capacity retention >63% (compared with the highest capacity 679 mAh g −1 ), offering enormous potential for energy storage applications.