Fe-induced carbon nanotube/amorphous carbon polyhedral frame for superior potassium storage

In todays energy field, the long-term development of lithium-ion batteries has been limited due to the scarcity and high cost of lithium resources. On the other hand, research towards of potassium-ion batteries (KIBs) is on the rise. Herein, we synthesize Fe-induced carbon nanotube/nitrogen-doped carbon (FNC) derived from metal-organic frameworks as a promising anode for KIBs. The carbon nanotubes can enhance the electronic conductivity and increase the contact area, thus improving the rate performance. Additionally, the amorphous carbon polyhedral frame can boost the electrochemical stability. Therefore, the FNC electrode exhibits a high reversible capacity (a charge capability of 268 mAh g^-1 after 200 cycles at 0.1 A g^-1) and an excellent rate performance.