Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
5439188 | Ceramics International | 2017 | 7 Pages |
Abstract
The siliconboron carbonitride/graphene (SiBCN/GN) composites were designed and synthesized by the insertion of GN sheets into the ceramic network of polymer-derived SiBCN via liquid dispersion (SiBCN/GN-ld) and solid phase blending (SiBCN/GN-sp) at 1100 °C. The composites were used as anode materials in lithium-ion batteries, and their electrochemical performances were investigated. Electrochemical measurements showed that the SiBCN/GN-ld exhibited a first cycle discharge capacity of 844.2 mA h gâ1 at a current density of 80 mA gâ1, which was higher than those of SiBCN/GN-sp, SiBCN, and GN anodes. The discharge capacity reduced to 347 mA h gâ1 and remained in this range over 30 cycles. SiBCN/GN-ld anode contained Si3N4, SiC, BNC, and free carbon nanocrystals sites, and GN acted as layered base supporting the SiBCN cluster, thus resulting in improved chemical stability and chemical electronic conductivity. Therefore, the SiBCN/GN-ld showed the improved electrochemical performances that were attributed to the presence of GN. GN layers acted as the supporting layers to stabilize the SiBCN matrix and alleviate the expansion of material structure during charge-discharge cycle. Dependence of the electrochemical capacities of the SiBCN/GN composites on their compositions and structures indicated the promising potential to enhance the electrochemical performances of the materials through molecular design and/or the control of the material structure.
Related Topics
Physical Sciences and Engineering
Materials Science
Ceramics and Composites
Authors
Sihui Wang, Xudong Hu, Yejing Dai,