In the current research project, we have prepared a novel Fe₃O₄@mesoporous carbon nanorod (denoted as Fe₃O₄@C) anode with yolk-shell structure for Li/Na-ion batteries via one-pot and surfactant-free synthesis strategy. The yolk-shell structure consists of Fe₃O₄ nanorod yolk completely protected by a well-conductive mesoporous carbon shell. The substantial void space in the Fe₃O₄@C yolk-shell nanorod can not only accommodate the full volume expansion of inner Fe₃O₄ nanorod, but also preserve the structural integrity of the Fe₃O₄@C anode and develop a stable SEI film on the outside mesoporous carbon shell during the repeated Li⁺/Na⁺ insertion/extraction processes. As for lithium storage, the Fe₃O₄@C electrode exhibits a high specific capacity (1247 mAh g⁻¹), stable cycling performance (a specific capacity of 954 mAh g⁻¹ after 200 cycles at a current density of 0.5 A g⁻¹) and excellent rate capability (specific capabilities of 1122, 958, 783, 577, and 374 mAh g⁻¹ at 0.5, 1, 2, 4, and 8 A g⁻¹, respectively). As for sodium storage, the Fe₃O₄@C yolk-shell nanorods also maintain a reversible capacity of approximate 424 mAh g⁻¹ at 0.1 A g⁻¹ after 100 cycles.

在当前的研究项目中，我们通过一锅法和无表面活性剂制备了一种新的具有卵黄壳结构的Fe ₃ O ₄ @卵黄碳纳米棒（表示为Fe ₃ O ₄ @C）阳极。综合策略。卵黄-壳结构由完全被导电性介孔碳壳保护的Fe ₃ O ₄纳米棒卵黄组成。Fe ₃ O ₄ @C卵黄壳纳米棒中的大量空隙空间不仅可以容纳内部Fe ₃ O ₄纳米棒的全部体积膨胀，而且可以保留Fe ₃ O ₄的结构完整性在重复的Li ⁺ / Na ⁺插入/萃取过程中，@ C阳极并在中介孔碳壳上形成稳定的SEI膜。对于锂存储，Fe ₃ O ₄ @C电极表现出高的比容量（1247 mAh g ^-1），稳定的循环性能（200次循环后在0.5 A g的电流密度下的比容量为954 mAh g ^-1）-1）和出色的速率能力（在0.5、1、2、4和8 A g ^-1时的比容量分别为1122、958、783、577和374 mAh g ^-1）。至于钠的储存，Fe ₃ O ₄100个循环后，C卵黄壳纳米棒在0.1 A g ^-1下也保持约424 mAh g ^-1的可逆容量。