We report the synthesis and application of a material composed of Fe 3 O 4 nanoparticles embedded in N‐doped graphene sheets (Fe 3 O 4 @N‐doped graphene) as a negative electrode for Li batteries. We study the influence of N‐doped graphene on the storage capacity of Fe 3 O 4 using different electrochemical techniques. The as‐prepared Fe 3 O 4 materials presented high‐quality crystalline nanostructures. The N‐doped graphene sheets improve the conductivity between the Fe 3 O 4 nanoparticles, allowing a faster charge transfer process than that for pure magnetite, as well as the presence of porous particles in the hybrid composite. The Fe 3 O 4 @N‐doped graphene material show the best Li storage capacity maintaining specific capacity values of 910 mA h g –1 during 150 cycles performed at 0.05 A g –1 and 850 mA h g –1 at 0.1 A g –1 during the following 50 cycles. The N‐doped graphene sheets resist the volume changes that occur during cycling processes in rate capability experiments. We provide a simple and novel method to obtain a material with a higher superficial area and conductivity between particles, allowing great performance as a negative electrode for Li batteries application.

中文翻译：

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嵌入N掺杂石墨烯中的Fe3O4纳米颗粒的增强的能量存储

我们报告了一种由嵌入到N掺杂石墨烯片中的Fe 3 O 4纳米颗粒组成的材料（Fe 3 O 4 @N掺杂石墨烯）作为锂电池负极的合成和应用。我们使用不同的电化学技术研究了N掺杂石墨烯对Fe 3 O 4储存容量的影响。所制备的Fe 3 O 4材料具有高质量的晶体纳米结构。N掺杂的石墨烯片改善了Fe 3 O 4纳米粒子之间的电导率，比纯磁铁矿的电荷转移过程更快，并且杂化复合材料中存在多孔颗粒。Fe 3 O 4 @N掺杂的石墨烯材料显示出最佳的Li储存容量，在0.05 A g –1和850 mA hg –1于0进行的150个循环中，保持比容量值为910 mA hg –1。在接下来的50个循环中，为1 A g –1。N掺杂石墨烯片可抵抗速率能力实验中循环过程中发生的体积变化。我们提供了一种简单新颖的方法来获得一种材料，该材料在颗粒之间具有较高的表面积和导电性，从而可作为锂电池应用的负极发挥出色的性能。