Co quantum dots embedded in modified montmorillonite loaded with graphitized carbon as an ultra-stable anode material for sodium-ion battery

Shiyue Cao; Xiaoting Xu; Qiming Liu; Hongyi Chen; Huijuan Zhu; Ye Lin

doi:10.1016/j.jcis.2023.07.064

Co quantum dots embedded in modified montmorillonite loaded with graphitized carbon as an ultra-stable anode material for sodium-ion battery

J Colloid Interface Sci. 2023 Nov 15;650(Pt B):1073-1085. doi: 10.1016/j.jcis.2023.07.064. Epub 2023 Jul 11.

Authors

Shiyue Cao¹, Xiaoting Xu¹, Qiming Liu², Hongyi Chen¹, Huijuan Zhu¹, Ye Lin¹

Affiliations

¹ Key Laboratory of Artificial Micro- and Nano-structures of Ministry of Education, School of Physics and Technology, Wuhan University, Wuhan 430072, China.
² Key Laboratory of Artificial Micro- and Nano-structures of Ministry of Education, School of Physics and Technology, Wuhan University, Wuhan 430072, China. Electronic address: qmliu@whu.edu.cn.

PMID: 37463533
DOI: 10.1016/j.jcis.2023.07.064

Abstract

Carbonaceous materials are competitive anodes in sodium-ion batteries (SIBs) due to their advantages, such as low cost, abundant active sites, and porosity. However, this type of material still suffers from slow rate capability and low capacity, which greatly hinders its application. In this work, the biomass-derived carbon is optimized based on a layered montmorillonite (Mt) skeleton and the cobalt quantum dots (Co QDs). A three-dimensional (3D) combination, specifically a 3D flower-like structure, of 0D material (Co QDs) and a two-dimensional (2D) material (Mt) has been achieved. The optimization and local limited effects of the Co QDs on the electronic properties have been demonstrated by density functional theory (DFT). The metallic Co QDs and carbon could form a Mott-Schottky junction, enhancing the conductivity and Na⁺ adsorption. Due to the synergetic improvement of structure and conductivity, the stripped Mt embedded with Co QDs loaded with nitrogen doped carbon (FMt@Co-NC) shows ultra-stable cycle stability (99.12% retention after 10,000 cycles at 10 A/g). This is the first time that Mt has been employed in high performance SIBs, which incubates a grand blueprint for effectively utilizing similar inactive energy-storage materials, through a simple and reliable approach.

Keywords: Cyclic stability; Graphitized carbon; Montmorillonite; Quantum dots; Sodium-ion batteries.