Over the past decades, metal selenides have drawn considerable attention due to their high theoretical specific capacity. However, huge volume changes and sluggish electrochemical transfer kinetics hinder their applications in energy storage and conversion. In this work, we demonstrate an efficient and ingenious synthesis strategy to regulate nickel selenide electrodes by the introduction of copper and in situ coating with carbon (Cu-NiSe₂@C). When used as anodes for lithium-ion batteries, the as-synthesized Cu-NiSe₂@C delivered a high capacity of 1630 mA h g⁻¹ at 1.0 A g⁻¹ after 200 cycles and excellent rate performance as well as long-term cycling stability with a high capacity of 489 mA h g⁻¹ at 10 A g⁻¹ after 20 000 cycles. When coupled with a commercial LiFePO₄ cathode, the full cells showed a high capacity of 463 mA h g⁻¹ at 0.2 A g⁻¹. Their superior electrochemical performance can be attributed to the synergistic effect of the in situ carbon coating and copper doping, which can promote the electron/ion transfer kinetics, as well as alleviate the volume expansion during cycling. This work will open new opportunities for the development of high-performance anodes for lithium storage.

中文翻译：

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通过铜掺杂和原位碳涂层对高速率和高能量密度锂离子半/全电池进行硒化镍的电子调制

在过去的几十年中，金属硒化物因其较高的理论比容量而备受关注。然而，巨大的体积变化和缓慢的电化学转移动力学阻碍了它们在能量存储和转化中的应用。在这项工作中，我们展示了一种有效而巧妙的合成策略，通过引入铜和碳原位涂层（Cu-NiSe ₂ @C）来调节硒化镍电极。合成后的Cu-NiSe ₂ @C用作锂离子电池的阳极时，经过200次循环后，在1.0 A g ^-1下可提供1630 mA hg ^-1的高容量，出色的倍率性能以及长期循环性能具有489 mA hg ^-1的高容量的稳定性20 000次循环后，在10 A g ^-1下。当与市售的LiFePO ₄阴极耦合时，满电池在0.2 A g ^-1下显示出463 mA hg ^-1的高容量。它们优异的电化学性能可归因于原位碳涂层和铜掺杂的协同作用，可促进电子/离子转移动力学，并减轻循环过程中的体积膨胀。这项工作将为开发用于锂存储的高性能阳极提供新的机会。