摘要
针对过渡金属硫化物(TMS)作为钠离子电池(SIBs)负极材料存在的导电性差、循环过程中体积膨胀导致容量衰减等问题,通过Fe掺杂及双碳源(碳纳米管CNTs与石墨相氮化碳g-C_(3)N_(4))协同策略,制备出Fe-Co_(3)S_(4)/SnS@CNTs@g-C_(3)N_(4)复合材料(sample1)。采用溶液共沉淀法合成Fe-CoSn(OH)_(6)前驱体,再经水热硫化与高温煅烧工艺,实现Fe掺杂的TMS与双碳网络复合。通过XRD、SEM、TEM、XPS及电化学等方法,分析sample1的结构及性能。结果表明,FeS2、Co_(3)S_(4)、SnS均匀嵌入CNTs与g-C_(3)N_(4)构筑的三维导电框架,有效缓解了电极材料体积膨胀问题,提升了电极材料中离子的传输效率。当m(CNTs)∶m(g-C_(3)N_(4))=1∶3时,sample1表现出最优的储钠性能,即在电流密度(j)为0.20,0.50 A/g下、循环500次后,sample1的质量比容量(C)的保持率分别为62.12%,61.18%,放电C=379.14,353.45 mA·h/g;在j=5.00 A/g(高倍率)下,sample1的C=284.70 mA·h/g,且在j恢复至0.05 A/g时,C回升至472.46 mA·h/g。协同优化网络显著降低了电荷转移阻抗,提升了Na+的扩散动力学。研究结果为高稳定性SIBs负极材料的设计提供新思路。
To address the issues of poor conductivity and capacity decay caused by volume expansion during cycling of transition metal sulfides(TMS)as anode materials for sodium-ion batteries,this study employs a synergistic strategy of Fe doping and dual carbon sources(carbon nanotubes,CNTs,and graphitic carbon nitride,g-C_(3)N_(4))to fabricate Fe-Co_(3)S_(4)/SnS@CNTs@g-C_(3)N_(4)composite materials.The Fe-CoSn(OH)_(6)precursor was synthesized using a solution co-precipitation method,followed by hydrothermal sulfidation and high-temperature calcination to integrate Fe-doped TMS with the dual carbon network.Structural and performance analyses of Sample 1 were conducted using XRD,SEM,TEM,XPS,and electrochemical methods.The results showed that FeS₂,Co_(3)S_(4),and SnS were uniformly embedded within a three-dimensional conductive framework constructed from CNTs and g-C_(3)N_(4),effectively alleviating volume expansion of the electrode mate‐rial and enhancing ion transport efficiency.When the mass ratio of CNTs to g-C_(3)N_(4)was 1∶3,Sample 1 exhib‐ited optimal sodium storage performance,with capacity retention rates of 62.12%and 61.18%after 500 cycles at current densities of 0.20 and 0.50 A/g,respectively,and discharge capacities of 379.14 and 353.45 mA·h/g.At a high rate of 5.00 A/g,Sample 1 maintained a capacity of 284.70 mA·h/g,which recovered to 472.46 mA·h/g when the current density returned to 0.05 A/g.The synergistic optimization of the network signifi‐cantly reduced charge transfer resistance and improved Na⁺diffusion kinetics.These findings provide new insights for the design of stable anode materials for sodium-ion batteries.
作者
杨云磊
马佳鑫
马天翼
张薇
赵钦
吴抒遥
孙颖
YANG Yunlei;MA Jiaxin;MA Tianyi;ZHANG Wei;ZHAO Qin;WU Shuyao;SUN Ying(School of Chemistry,Liaoning University,Shenyang 110036,China;School of Science,RMIT University,Melbourne VIC 3000,Australia)
出处
《宁夏大学学报(自然科学版中英文)》
2025年第3期267-278,共12页
Journal of Ningxia University(Natural Science Edition in Chinese and English)
基金
国家自然科学基金企业联合基金重点项目(U24B20198)
国家自然科学基金青年项目(22308139)
辽宁省教育厅基本科研面上项目(JYTMS20230767)。
