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钾离子电池因其较高的能量密度和丰富的钾资源,具有成为大规模储能设备的潜力.但钾离子的半径较大引起的可逆容量低和循环稳定性等问题限制了钾离子电池的实际应用.在本项工作中,我们将前驱体细菌纤维素浸泡在作为造孔剂和掺杂剂的Mg(NO3)2溶液中,经炭化和酸洗处理后,制备出氮掺杂细菌纤维素基炭材料(NBCC).该材料有相互连接的多孔网络结构、均匀的N元素分布(原子占比3.38％)以及高表面积等特点(1355 m2 g?1).同时,探究了Mg(NO3)2溶液浓度对材料形貌、孔隙率、N掺杂量和电化学性能的影响.经过性能优化,NBCC作为钾离子电池负极在5 A g?1的大电流密度下,可逆容量可达134 mAh g?1;在2 A g?1的电流密度下,循环2500圈后,比容量仍保持为307 mAh g?1.以NBCC作为负极组装的钾离子混合电容器,在能量密度为166 Wh kg?1时,具有493 W kg?1的功率密度,循环2000圈后仍具有95％的容量保持率,证明了该材料具有很强的实际应用潜力.本工作通过简便的合成方法制备的炭负极材料表现出良好的电化学性能,有望促进绿色、大规模储能设备的发展.“,”Potassium-ion batteries (PIBs) have the potential to be used in future large-scale energy storage devices because of the abundance of potassium resources and their relatively high energy density. However, low reversible capacity and poor cycling stabil-ity caused by the large size of the potassium ions limit their practical application. N-doped bacterial cellulose-derived carbons (NBCCs) were prepared by impregnating bacterial cellulose with Mg(NO3)2 solutions (0.03, 0.05 and 0.07 mol L?1) as a pore tem-plate and nitrogen source, followed by carbonization and acid washing. The effects of the Mg(NO3)2 concentration on the morpho-logy, porosity, N doping level and electrochemical performance of the NBCCs were investigated. NBCC (0.05) is the best of the three because it has an interconnected pore network structure with a homogeneous distribution of N at a concentration of 3.38 at％and a high specific surface area of 1355 m2 g?1. It delivers an excellent rate capability of 134 mAh g?1 at 5 A g?1 and a capacity of 307 mAh g?1 after 2500 cycles at 2 A g?1. A NBCC (0.05)-based anode in a potassium ion hybrid capacitor has a high energy dens-ity of 166 W h kg?1 at a power density 493 W kg?1 and excellent cyclability with a capacity retention of nearly 95％ after 2000 cycles. This simple synthesis strategy for fabricating carbon anode materials with an excellent electrochemical performance should promote the development of green and large-scale energy storage devices.