Fe-Induced Carbon Nanotube/Amorphous Carbon Polyhedral Frame for Superior Potassium Storage.

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