A facile strategy of the one-step arc-discharge was applied to have synthesized the dual-functional N-doped graphite coated Ni (Ni@CN) nanocapsules in this study. And their microstructure, surface compositions, catalytic properties, and microwave absorption performance were investigated. The results reveal that the Ni@CN nanocapsules show superior electrocatalytic activities in the hydrogen evolution reaction (HER). The Ni@CN nanocapsules only require an overpotential of 85 mV at the current density of 10 mA cm^-2, and their Tafel slope is 60 mV dec^-1. Moreover, the Ni@CN nanocapsules exhibit excellent microwave absorption performance as microwave absorbers. Their optimal value of reflection loss (RL) is -35.8 dB at 11.7 GHz with a thickness of 2.3 mm. The strong synergistic effect between the N-doped graphite shell and Ni core makes the Ni@CN nanocapsules have excellent dual-functional performance in catalytic and microwave absorption. Hence, the Ni@CN is a promising candidate for energy supplying materials and microwave absorbers in the future.

本研究采用一种简便的单步电弧放电策略，合成了双功能掺氮石墨包覆的镍（Ni @ CN）纳米胶囊。并研究了它们的微观结构，表面组成，催化性能和微波吸收性能。结果表明，Ni @ CN纳米胶囊在析氢反应（HER）中显示出优异的电催化活性。Ni @ CN纳米胶囊在10 mA cm ^-2的电流密度下仅需要85 mV的超电势，并且它们的Tafel斜率是60 mV dec ^-1。而且，Ni @ CN纳米胶囊作为微波吸收剂表现出优异的微波吸收性能。反射损耗（RL）在11.7 GHz时的最佳值为-35.8 dB，厚度为2.3 mm。N掺杂石墨壳与Ni核之间的强大协同作用使Ni @ CN纳米胶囊在催化和微波吸收方面具有出色的双重功能。因此，Ni @ CN在将来成为能量供应材料和微波吸收器的有前途的候选者。