Transition metal oxide MnFe₂O₄ is considered a promising anode material for Li-ion batteries owing to its high theoretical specific capacity. However, this material has two bottleneck problems, i.e., poor conductivity and serious volume expansion during cycling. In this work, MnFe₂O₄ nanoparticles were successfully encapsulated in the matrix of N-doped porous carbon via a sol–gel method. As a result, the N-doped carbon matrix enhances the electronic conductivity of the composites. The special porous structure increases the contact area between the electrode material and the electrolyte and facilitates the rapid infiltration of the electrolyte. At a calcination temperature of 400 °C, the MnFe₂O₄/C composite shows a high initial discharge specific capacity of 1207.0 mAh g⁻¹ at 0.2 A g⁻¹ and retains a reversible specific capacity of 1100.1 mAh g⁻¹ after 200 cycles. The simple design of metal oxide nanomaterials encapsulated in N-doped porous carbon provides a new direction for improving the electrochemical performance of electrode materials for Li-ion batteries.

Graphical Abstract

A brief abstract: MnFe₂O₄ nanoparticles were successfully encapsulated in the matrix of N-doped porous carbon via a sol–gel method. At a calcination temperature of 400 °C, the MnFe₂O₄/C composite shows a high initial discharge specific capacity of 1207.0 mAh g⁻¹ at 0.2 C and retains a reversible specific capacity of 1100.1 mAh g⁻¹ after 200 cycles.

中文翻译：

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N 掺杂多孔碳封装 MnFe2O4 纳米粒子作为锂离子电池的高级阳极

过渡金属氧化物MnFe ₂ O ₄由于其高理论比容量而被认为是一种有前途的锂离子电池负极材料。然而，该材料存在两个瓶颈问题，即导电性差和循环过程中体积膨胀严重。在这项工作中，通过溶胶-凝胶方法成功地将MnFe ₂ O ₄纳米颗粒封装在N掺杂多孔碳基质中。因此，氮掺杂碳基体增强了复合材料的电子电导率。特殊的多孔结构增加了电极材料与电解液的接触面积，有利于电解液的快速渗透。在400℃的煅烧温度下，MnFe ₂ O ₄ /C复合材料在0.2 A g ^{-1下表现出1207.0 mAh g -1}的高初始放电比容量，并在200年后保持1100.1 mAh g ^-1的可逆比容量。循环。封装在氮掺杂多孔碳中的金属氧化物纳米材料的简单设计为提高锂离子电池电极材料的电化学性能提供了新的方向。

图形概要

摘要：通过溶胶-凝胶方法成功地将 MnFe ₂ O ₄纳米粒子封装在氮掺杂多孔碳基质中。在400℃的煅烧温度下，MnFe ₂ O ₄ /C复合材料在0.2C下表现出1207.0mAh g ^-1的高初始放电比容量，并在200次循环后保持1100.1mAh g ^-1的可逆比容量。