A novel hierarchical architecture—N-doped hollow carbon fibers decorated with N-doped carbon clusters (NHCF@NCC)—was synthesized for high-performance anode material of potassium ion batteries (PIBs). The material is formulated with porous N-doped hollow carbon fibers as the backbone, which effectively shortens the diffusion length of potassium ion and increases the interface between the electrode and electrolyte. In addition, the N-doped carbon clusters attached on the hollow carbon fibers can provide abundant reactive sites. Specially, NHCF@NCC could form a freestanding electrode with a three dimensional interconnected conductive network owing to the ultrahigh aspect ratio. In this way, NHCF@NCC delivers an excellent electrochemical performance as free-standing anode materials of PIBs, exhibiting a high reversible capacity of 310 mA h g⁻¹ at a current density of 100 mA g⁻¹, a long cycling stability of 1000 cycles with negligible degradation, and a superior rate performance of 153 mA h g⁻¹ at a large current density of 2000 mA g⁻¹.

合成了一种新颖的分层体系结构-装饰有N掺杂碳簇（NHCF @ NCC）的N掺杂中空碳纤维-用于钾离子电池（PIB）的高性能负极材料。该材料以多孔的N掺杂空心碳纤维为骨架，有效地缩短了钾离子的扩散长度并增加了电极与电解质之间的界面。另外，附着在中空碳纤维上的N掺杂碳簇可以提供丰富的反应位点。特别地，由于超高纵横比，NHCF @ NCC可以形成具有三维互连导电网络的独立电极。这样，NHCF @ NCC作为PIB的独立阳极材料可提供出色的电化学性能，并具有310 mA hg的高可逆容量^-1在100mA g的电流密度^-1，1000个循环具有可忽略的劣化的长循环稳定性，和153毫安Hg的优良率性能^-1处的2000毫安克的大电流密度^-1。