Ultra-High Pyridinic N-Doped Porous Carbon Monolith Enabling High-Capacity K-Ion Battery Anodes for Both Half-Cell and Full-Cell Applications

An ultrahigh pyridinic N-content-doped porous carbon monolith is reported, and the content of pyridinic N reaches up to 10.1% in overall material (53.4 +/- 0.9% out of 18.9 +/- 0.4% N content), being higher than most of previously reported N-doping carbonaceous materials, which exhibit greatly improved electrochemical performance for potassium storage, especially in term of the high reversible capacity. Remarkably, the pyridinic N-doped porous carbon monolith (PNCM) electrode exhibits high initial charge capacity of 487 mAh g(-1) at a current density of 20 mA g(-1), which is one of the highest reversible capacities among all carbonaceous anodes for K-ion batteries. Moreover, the K-ion full cell is successfully assembled, demonstrating a high practical energy density of 153.5 Wh kg(-1). These results make PNCM promising for practical application in energy storage devices and encourage more investigations on a similar potassium storage system.