中空FeS2/NiS2/Ni3S2@NC立方体复合材料的制备及其电化学性能
Preparation and Electrochemical Properties of Hollow FeS2/NiS2/Ni3S2@NC Cube Composites
刘莹 1陈平 1周雪 1孙晓杰 1王瑞琪1
作者信息
- 1. 大连理工大学化工学院精细化工重点实验室 大连 116024
- 折叠
摘要
以Cu2O立方体为自牺牲模板,进行协同刻蚀-沉淀(CEP)路线、高温煅烧、聚多巴胺(PDA)涂层包覆和高温硫化,制备出中空FeS2/NiS2/Ni3S2@NC纳米立方体复合材料并研究其电化学性能.结果表明,通过CEP路线并引入Ni和Fe金属元素,制备过程较为简单和安全.这种材料的中空立方体结构,能抑制体积膨胀和减小锂离子嵌入脱出产生的机械应力.引入N掺杂碳层(NC)能极大地提高材料的导电性和结构稳定性,更好地维持立方体结构.在电流密度为0.2A·g-1的条件下经过100次循环后,FeS2/NiS2/Ni3S2@NC纳米立方体复合材料的放电比容量保持在899.4 mAh·g-1,表明其具有较高的比容量、良好的循环稳定性和倍率性能(3.0A·g-1电流密度下比容量为427.5 mAh·g-1).
Abstract
A novel composite hollow FeS2/NiS2/Ni3S2@NC cube is synthesized through collaborative etch-precipitation(CEP)route,high-temperature calcination,polydopamine coating and high-temperature vulcanization with a pre-prepared Cu2O cube as sacrificial template.The preparation process is safe,while Ni and Fe are successfully incorporated through the CEP route.The hollow cube structure can ef-fectively restrain the volume expansion and slow down the mechanical stress caused by lithium-ion em-bedding and release.The introduction of N-doped carbon layer(NC)can greatly improve the conductivity and structural stability of the composite material,so that it can better maintain the stability of the cube structure.Furthermore,after 100 cycles at a current density of 0.2 A·g-1,the specific discharge capacity of the FeS2/NiS2/Ni3S2@NC cube composite can be maintained at 899.4 mAh·g-1,showing high specific capacity,good cycle stability,and great rate performance(427.5 mAh·g-1 at 3.0 A·g-1).
关键词
复合材料/锂离子电池/负极材料/过渡金属硫化物Key words
composite/lithium-ion batteries/anode materials/transition metal sulfides引用本文复制引用
基金项目
兴辽英才项目(XLYC1802085)
国家自然科学基金(51873109)
大连市科技创新基金重大项目(2019J11CY007)
出版年
2024
NETL
NSTL
万方数据