AUTHOR=Xue Kaiwen , Si Yechen , Xie Shuya , Yang Jingxuan , Mo Yan , Long Baojun , Wei Wen , Cao Peiyu , Wei Huixian , Guan Hongyu , Michaelis Elizabeth G. , Guo George , Yue Yanfeng , Shan Changsheng TITLE=Free-Standing N-Doped Porous Carbon Fiber Membrane Derived From Zn–MOF-74: Synthesis and Application as Anode for Sodium-Ion Battery With an Excellent Performance JOURNAL=Frontiers in Chemistry VOLUME=Volume 9 - 2021 YEAR=2021 URL=https://www.frontiersin.org/journals/chemistry/articles/10.3389/fchem.2021.647545 DOI=10.3389/fchem.2021.647545 ISSN=2296-2646 ABSTRACT=It is important to develop new energy storage and conversion technology to meet the energy crisis for the sustainable development of human society. In this work, a free-standing porous nitrogen-doped carbon fibers (PN-CFs) membranes were obtained from the pyrolysis of Zn-MOF-74/polyacrylonitrile (PAN) composite fibers, which were in-situ fabricated by electrospinning technology. The resulting free-standing fiber can be cut into membrane disks and directly used as anode electrode without the use of any binder or additive. The PN-CFs showed great reversible capacities of 210 mAh g−1 at current density of 0.05 A g−1 and an excellent cyclic stability of 170.5 mAh g−1 at current density of 0.2 A g-1 after 600 cycles in sodium-ion batteries (SIBs). The improved electrochemical performance of PN-CFs can be attributed to the rich porous structure derived by incorporated Zn-MOF-74 and nitrogen doping to promote the sodium ions transportation.