Micron-sized SiO x /N-doped carbon composite spheres fabricated with biomass chitosan for high-performance lithium-ion battery anodes

Dajin Liu; Zhipeng Jiang; Wei Zhang; Jingqi Ma; Jia Xie

doi:10.1039/d0ra07029g

Micron-sized SiO _x /N-doped carbon composite spheres fabricated with biomass chitosan for high-performance lithium-ion battery anodes

RSC Adv. 2020 Oct 20;10(63):38524-38531. doi: 10.1039/d0ra07029g. eCollection 2020 Oct 15.

Authors

Dajin Liu^{1

2}, Zhipeng Jiang^{1

2}, Wei Zhang¹, Jingqi Ma^{1

2}, Jia Xie¹

Affiliations

¹ State Key Laboratory of Advanced Electromagnetic Engineering and Technology, School of Electrical and Electronic Engineering, Huazhong University of Science and Technology Wuhan 430074 China xiejia@hust.edu.cn.
² State Key Laboratory of Materials Processing and Die & Mould Technology, School of Materials Science and Engineering, Huazhong University of Science and Technology Wuhan 430074 China.

Abstract

To achieve superior lithium storage performance, SiO _x is usually designed into nanostructured SiO _x /C composites by complex or expensive methods. Here, micron-sized interconnected SiO _x /N-doped carbon (NC) microspheres composed of evenly dispersed SiO _x nano-domains and NC have been fabricated by a scalable microemulsion method and following pyrolysis, using vinyltriethoxysilane and chitosan as precursors. The unique structure of the micron-sized SiO _x /NC spheres leads to enhanced structural integrity and enables stable long-term cycling (800 cycles at 2 A g^-1). Benefiting from the enhanced electron/Li⁺ diffusion kinetics originated from the unique structure and N-doping, SiO _x /NC-2 presents considerable capacitive-controlled Li storage capacity, which leads to outstanding rate capability. Consequently, the assembled SiO _x /NC-2//LiFePO₄ full cell exhibits superior rate capability (106 mA h g^-1 at 4C) and stable long-term cycling at 2C (102 mA h g^-1 after 350 cycles). This work opens a new door for the application of chitosan in building micron-sized high-performance SiO _x /C anode materials, and to some extent facilitates the recycling of waste seafood shells.