室温固相反应助力制备氮硫共掺杂碳限域的FeCoS2复合物用于高性能钠离子电池负极
Room-temperature solid-state reaction-assisted strategy to fabricate nanocomposites of N,S-codoped carbon confined FeCoS2 as high-performance anode materials for sodium-ion batteries
马文龙 1刘桑鑫 1周钺 2吴平 1曹鑫 1朱晓舒 3魏少华 1周益明1
作者信息
- 1. 南京师范大学化学与材料科学学院,江苏省新型动力电池重点实验室,南京 210023
- 2. 南京晓庄学院环境科学学院,南京 211171
- 3. 南京师范大学分析测试中心,南京 210023
- 折叠
摘要
利用室温固相自组装反应制备Co(Ⅱ)和Fe(Ⅱ)双席夫碱配合物,随后在硫粉存在下中温热处理,使该配合物同时发生热解碳化和固相硫化反应,从而获得N、S共掺杂碳限域的FeCoS2纳米复合物(记为FeCoS2⊂NSC).通过粉末X射线衍射、透射电镜、X射线光电子能谱和热重分析技术分别对纳米复合物的物相、形貌结构、组分和含量等进行物理表征,并通过循环伏安、恒电流充放电技术测试其电化学储钠性能.研究结果表明,最优化条件下制备的复合物(FeCoS2⊂NSC-7001)中FeCoS2粒子的平均尺寸约为3.4 nm,且被均匀限域在N、S共掺杂的碳基体中;该复合物作为钠离子电池负极时,在0.1 A·g-1的电流密度下经过300次充放电循环,其可逆充电比容量仍高达310.4 mAh·g-1;即使在5 A·g-1的大电流密度下,其充电比容量也高达146.0 mAh· g-1,呈现优异的电化学储钠性能.
Abstract
In this work,a facile and cost-effective solid-state reaction method for the synthesis of the nanocompos-ites(denoted as FeCoS2CNSC)of N,S-codoped carbon-confined FeCoS2 nanocrystalline was presented.By directly mixing cobalt acetate tetrahydrate,ferrous acetate,o-vanilin and o-phenylenediamine with a molar ratio of 1:1:4:2 at ambient temperature in the presence of sulfur powder,a self-assembly solid state reaction took place to give rise to the complexes of Co(Ⅱ)and Fe(Ⅱ)with a bis-Schiff base,which were evenly distributed in the sulfur powder sur-roundings.After subsequent annealing at an elevated temperature,simultaneous carbonization and sulfidization occurred,resulting in the in-situ formation of ultrafine FeCoS2 nanoparticles confined in N,S-codoped carbon matri-ces.The phase,morphology,composition,and content of each component in the nanocomposite were determined by powder X-ray diffraction,transmission electron microscopy,X-ray photoelectron spectroscopy,and thermogravimet-ric analysis.The electrochemical sodium storage performance was tested by the cyclic voltammetry and galvanostat-ic charge-discharge techniques.The results showed that the average size of the FeCoS2 particles in the optimized nanocomposite(FeCoS2 CNSC-7001)was ca.3.4 nm,which was uniformly confined in the N,S-codoped carbon matrices.When FeCoS2CNSC-7001 was used as an anode material for sodium-ion batteries,it exhibited excellent electrochemical energy storage performance in terms of long-term cycling stability and rate capability.An anode pre-pared with FeCoS2 CNSC-7001 nanocomposite exhibited significantly improved sodium-ion storage performance,where a large reversible charging capacity of 310.4 mAh-g-1 was obtained after 300 cycles at a current density of 0.1 A·g-1.Even when such an anode was cycled at a current density of 5 A·g-1,a reversible specific charging capac-ity of 146.0 mAh·g-1 can still be achieved,showing excellent electrochemical sodium storage performance.
关键词
钠离子电池/负极材料/FeCoS2纳米晶/N、S共掺杂碳材料/纳米复合物/室温固相反应Key words
sodium-ion batteries/anode materials/FeCoS2 nanocrystalline/N,S-codoped carbon material/nanocomposites/room-temperature solid-state reaction引用本文复制引用
基金项目
国家自然科学基金(22004070)
国家自然科学基金(52072181)
出版年
2024
NETL
NSTL
万方数据