CIESC Journal ›› 2022, Vol. 73 ›› Issue (12): 5625-5637.DOI: 10.11949/0438-1157.20221116

• Material science and engineering, nanotechnology • Previous Articles     Next Articles

Preparation and lithium storage performance of K+-doped spinel (Co0.2Cr0.2Fe0.2Mn0.2Ni0.2)3O4 high-entropy oxide anode materials

Pengpeng WANG(), Yanggang JIA, Xia SHAO, Jie CHENG, Aiqin MAO(), Jie TAN, Daolai FANG   

  1. Key Laboratory of Green Fabrication and Surface Technology of Advanced Metal Materials, Ministry of Education, School of Materials Science and Engineering, Anhui University of Technology, Ma’anshan 243032, Anhui, China
  • Received:2022-08-08 Revised:2022-11-01 Online:2023-01-17 Published:2022-12-05
  • Contact: Aiqin MAO

K+掺杂尖晶石型(Co0.2Cr0.2Fe0.2Mn0.2Ni0.23O4高熵氧化物负极材料制备与储锂性能研究

王朋朋(), 贾洋刚, 邵霞, 程婕, 冒爱琴(), 檀杰, 方道来   

  1. 安徽工业大学材料科学与工程学院,先进金属材料绿色制备与表面技术教育部重点实验室,安徽 马鞍山 243032
  • 通讯作者: 冒爱琴
  • 作者简介:王朋朋(1995—),男,硕士研究生,wang_pengpeng2022@163.com
  • 基金资助:
    安徽省自然科学基金项目(2008085ME125);先进金属材料绿色制备与表面技术教育部重点实验室主任基金项目(GFST2022ZR08);安徽省高校自然科学研究重点项目(KJ2020A0268)

Abstract:

A series of inactive K+-doped spinel-type (K x CoCrFeMnNi)3/(5+x)O4 (x=0, 0.5, 1, 1.5) high-entropy oxides lithium-ion battery anode materials were successfully synthesized by solution combustion method, and the effects of K+ doping on the structure and lithium storage performance were systematically investigated. The results show that all the synthesized nanocrystalline powders are crystallized as single spinel structure with the increase of K+ doping. Among them, the equimolar K+-doped (K1/6Co1/6Cr1/6Fe1/6Mn1/6Ni1/6)3O4 high-entropy oxide anode material has the highest specific capacity, excellent cycling stability and rate capability. The initial specific discharge capacity of (K1/6Co1/6Cr1/6Fe1/6Mn1/6Ni1/6)3O4 is 1295 mA·h·g-1 at the current density of 200 mA·g-1 with columbic efficiency of 78%. The specific capacity decreases first and then increases as the cycle proceeds, and after 150 cycles the reversible specific capacity increases to 1505 mA·h·g-1. Even at a high current density of 1000 mA·g-1, it still has a reversible specific capacity of 1402 mA·h·g-1 after 500 cycles, which is much higher than the theoretical specific capacity of 898 mA·h·g-1. Although the doping of low-valent inactive K+ decreases the lattice constant due to the charge compensation effect, entropy-stabilized crystal structure improves the cycling stability, and the abundant surface oxygen vacancies, small grain size and mesoporous structure are beneficial to improve the pseudocapacitive contribution and electron/ion diffusion ability, which significantly improve the specific capacity and rate performance of the as-synthesized (K1/6Co1/6Cr1/6Fe1/6Mn1/6Ni1/6)3O4 anode material.

Key words: lithium-ion batteries anode materials, inactive K+ doping, high-entropy oxide, spinel structure, nanomaterials, electrochemistry, kinetics

摘要:

通过溶液燃烧法成功合成了一系列非活性K+掺杂的尖晶石型 (K x CoCrFeMnNi)3/(5+x)O4(x=0,0.5,1,1.5)高熵氧化物锂离子电池负极材料,系统研究了K+掺杂对结构和储锂性能的影响。结果表明:随着K+掺杂量的增加,均可制备出具有单一尖晶石结构的纳米晶粉体材料,其中等摩尔K+掺杂的 (K1/6Co1/6Cr1/6Fe1/6Mn1/6Ni1/6)3O4高熵氧化物负极材料具有最高的比容量、优异的循环稳定性和倍率性能。(K1/6Co1/6Cr1/6Fe1/6Mn1/6Ni1/6)3O4电极在200 mA·g-1电流密度下,首次放电比容量为1295 mA·h·g-1(首次库仑效率78%);随着循环的进行,可逆比容量先降低后增加,循环150次可逆比容量增加至1505 mA·h·g-1;即使在1000 mA·g-1大电流密度下循环500次后仍具有1402 mA·h·g-1的可逆比容量(均高于理论比容量898 mA·h·g-1)。低价非活性K+的掺杂由于电荷补偿效应使晶格常数降低,但高构型熵稳定的晶体结构提高了循环稳定性;丰富的表面氧空位、较小的晶粒尺寸和介孔结构,增加了赝电容贡献率和电子/离子传输能力,从而显著提升了材料的比容量和倍率性能。

关键词: 锂离子电池负极材料, 非活性K+掺杂, 高熵氧化物, 尖晶石结构, 纳米材料, 电化学, 动力学

CLC Number: