Pore structure regulation of hard carbon: Towards fast and high-capacity sodium-ion storage

Le Yang; Mingxiang Hu; Hongwei Zhang; Wen Yang; Ruitao Lv

doi:10.1016/j.jcis.2020.01.085

Pore structure regulation of hard carbon: Towards fast and high-capacity sodium-ion storage

J Colloid Interface Sci. 2020 Apr 15:566:257-264. doi: 10.1016/j.jcis.2020.01.085. Epub 2020 Jan 23.

Authors

Le Yang¹, Mingxiang Hu², Hongwei Zhang², Wen Yang³, Ruitao Lv⁴

Affiliations

¹ Key Laboratory of Cluster Science of Ministry of Education Beijing Key Laboratory of Photoelectronic/Electrophotonic Conversion Materials, School of Chemistry and Chemical Engineering, Beijing Institute of Technology, Beijing 100081, China; State Key Laboratory of New Ceramics and Fine Processing, School of Materials Science and Engineering, Tsinghua University, Beijing 100084, China.
² State Key Laboratory of New Ceramics and Fine Processing, School of Materials Science and Engineering, Tsinghua University, Beijing 100084, China.
³ Key Laboratory of Cluster Science of Ministry of Education Beijing Key Laboratory of Photoelectronic/Electrophotonic Conversion Materials, School of Chemistry and Chemical Engineering, Beijing Institute of Technology, Beijing 100081, China. Electronic address: [email protected].
⁴ State Key Laboratory of New Ceramics and Fine Processing, School of Materials Science and Engineering, Tsinghua University, Beijing 100084, China; Key Laboratory of Advanced Materials (MOE), School of Materials Science and Engineering, Tsinghua University, Beijing 100084, China. Electronic address: [email protected].

PMID: 32007737
DOI: 10.1016/j.jcis.2020.01.085

Abstract

Hard carbon is regarded as one of the most promising anode material for sodium-ion batteries in virtue of the low cost and stable framework. However, the correlation between pore structures of hard carbon and sodium-ion storage is still ambiguous. In this work, based on precise control of pore-size distribution, the capacity, ion diffusion, and initial Coulombic efficiency were improved. Meanwhile, the relationship between pore structure and capacity was investigated. Our result indicates that the micropores hinder ion diffusion and hardly ever accommodate Na⁺ ions, while mesopores facilitate Na⁺ ion intercalation. Hard carbon with negligible micropores and abundant mesopores delivers a maximum capacity of 283.7 mAh g^-1 at 20 mA g^-1, which is 83% higher than that of micropore-rich one. Even after 320 cycles at 200 mA g^-1, the capacity still remains 189.4 mAh g^-1.

Keywords: Anode; Hard carbon; Mesopore; Micropore; Pore-structure evolution; Sodium-ion battery.