B-incorporated, N-doped hierarchically porous carbon nanosheets as anodes for boosted potassium storage capability

Carbonaceous nanomaterials with porous structure have become the highly promising anode materials for potassium-ion batteries (PIBs) due to their abundant resources, low-cost, and excellent conductivity. Nevertheless, the sluggish reaction kinetics and inferior cycling life caused by the large radius of K ions severely restrict their commercial development. Herein, B,N co-doped hierarchically porous carbon nanosheets (BNPC) are achieved via a facile template-assisted route, followed by a simple one-step carbonization process. The resultant BNPC possesses a unique porous structure, large surface area, and high-level B,N co-doping. The structural features endows it with remarkable potassium storage performances, which delivers a high reversible capacity (242.2 mAh/g at 100 mA/g after 100 cycles), and long cycling stability (123.1 mAh/g at 2000 mA/g and 62.9 mAh/g at 5000 mA/g after 2000 cycles, respectively). Theoretical simulations further validate that the rich B doping into N-modified carbon configuration can greatly boost the potassium storage capability of the BNPC anode. (C) 2021 Published by Elsevier B.V. on behalf of Chinese Chemical Society and Institute of Materia Medica, Chinese Academy of Medical Sciences.