The shortcoming of Fe‐based materials, their poor electron transfer efficiency, restricts their electrochemical performance severely. An electric field (E) is induced by an Fe₇S₈/α‐FeOOH nano‐heterostructure (SACF) via two simple immersion steps at room temperature. The charge transfer from α‐FeOOH to Fe₇S₈ spontaneously establishes an intrinsic electric field at the Fe₇S₈/α‐FeOOH nano‐heterostructure boundary. Additionally, the relationship between structure and property is investigated by structural characterization and density functional theory calculations that are used to explain the electron transfer mechanism and good wettability in KOH electrolyte. The results indicate that the electric field accelerates the electron transfer rate during charge/discharge process, provides the most of active materials (both Fe₇S₈ and α‐FeOOH) and facilitates the contact of active material with electrolyte. When used as the supercapacitor negative electrode, the SACF delivers superior specific capacity of 520.27 F g⁻¹ at 1 A g⁻¹ current density, 2.5 times that of the ACF (α‐FeOOH nanosheet array), and shows excellent cycle life and rate capacity. This work introduces the consideration of electric field into fabricating an effective supercapacitor negative electrode, and helps to understand the function mechanism of nano‐heterojunction when designed in electrode materials.

中文翻译：

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电场辅助的增强电子转移，可提高制备的Fe7S8 /α-FeO​​OH纳米异质结构的超级电容器负极性能。

铁基材料的缺点是电子传输效率差，严重限制了它们的电化学性能。Fe ₇ S ₈ /α-FeO​​OH纳米异质结构（SACF）在室温下通过两个简单的浸入步骤感应出电场（E）。从α-FeO​​OH到Fe ₇ S ₈的电荷转移自发地在Fe ₇ S ₈处建立了固有电场/α-FeO​​OH纳米异质结构边界。此外，还通过结构表征和密度泛函理论计算研究了结构与性能之间的关系，这些计算可用来解释KOH电解质中的电子转移机理和良好的润湿性。结果表明，电场加速了充电/放电过程中的电子传输速率，提供了最多的活性物质（Fe ₇ S ₈和α-FeO​​OH），并促进了活性物质与电解质的接触。当用作超级电容器负极时，SACF在1 A g ^-1时可提供520.27 F g ^-1的出色比容量电流密度是ACF（α-FeO​​OH纳米片阵列）的2.5倍，并具有出色的循环寿命和倍率能力。这项工作将电场的考虑引入到制造有效的超级电容器负极中，并有助于理解在电极材料中进行设计时纳米异质结的作用机理。