Metal-Organic Framework@Polyacrylonitrile-Derived Potassiophilic Nanoporous Carbon Nanofiber Paper Enables Stable Potassium Metal Anodes

Potassium (K) metal is a promising anode for potential low-cost and high-energy-density K-ion batteries. However, its application is hampered by serious dendrite growth and large volume change. Herein, a Co nanoparticle-embedded nitrogen-doped nanoporous carbon nanofiber paper is prepared by carbonizing the electrospun fiber paper of metal-organic framework (MOF) nanoparticles and polyacrylonitrile, which displays a high potassiophilicity due to the incorporation of Co nanoparticles and N doping. As a three-dimensional host, excellent electrochemical performance is demonstrated for the K metal anode with a high average Coulombic efficiency of 98.75% for 400 cycles and a long lifespan of 1300 h in symmetric cells. Furthermore, enhanced electrochemical performance with good cycling stability and rate capability is achieved in full cells that are paired with organic cathodes. Our findings highlight a promising strategy for fabricating high-performance K metal anodes using MOF-based materials.

Automated summary

A Co nanoparticle-embedded nitrogen-doped nanoporous carbon nanofiber paper is prepared as a host material for potassium metal anodes, demonstrating excellent electrochemical performance with high Coulombic efficiency and long lifespan. Furthermore, when paired with organic cathodes, enhanced electrochemical performance with good cycling stability and rate capability is achieved.