Open AccessHomogeneous Elongation of N‐Doped CNTs over Nano‐Fibrillated Hollow‐Carbon‐Nanofiber: Mass and Charge Balance in Asymmetric Supercapacitors Is No Longer Problematic
Author(s) -
Kim Taewoo,
Subedi Subhangi,
Dahal Bipeen,
Chhetri Kisan,
Mukhiya Tanka,
Muthurasu Alagan,
Gautam Jagadis,
Lohani Prakash Chandra,
Acharya Debendra,
Pathak Ishwor,
Chae SuHyeong,
Ko Tae Hoon,
Kim Hak Yong
Publication year - 2022
Publication title -
advanced science
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 5.388
H-Index - 100
ISSN - 2198-3844
DOI - 10.1002/advs.202200650
Subject(s) - supercapacitor , materials science , capacitance , anode , carbon nanotube , cathode , nanofiber , carbon nanofiber , nanotechnology , carbon fibers , nanoparticle , electrode , chemical engineering , composite material , composite number , chemistry , engineering
The hurdle of fabricating asymmetric supercapacitor (ASC) devices using a faradic cathode and a double layer anode is challenging due to the required large amount of active mass of anodic material compared to that of the cathodic material during mass balancing due to the large difference in capacitance values of the two electrodes. Here, the problem is addressed by engineering a negative electrode that furnishes an ultrahigh capacitance. An in situ developed metal–organic framework (MOF)‐based thermal treatment is adopted to grow highly porous N‐doped carbon nanotubes (CNTs) containing submerged Co nanoparticles over nano‐fibrillated electrospun hollow carbon nanofibers (HCNFs). The optimized CNT@HCNF‐1.5 furnishes an ultrahigh capacitance approaching 712 F g –1 with excellent rate capability. The capacitance reported from this work is the highest for any carbonaceous material reported to date. The CNT@HCNF‐1.5 is further used to fabricate symmetric supercapacitors (SSCs), as well as ASC devices. Remarkably, both the SSC and ASC devices furnish incredible performances in all aspects of SCs, such as a high energy density, long cycle life, and high rate capability, displaying decent practical applicability. The energy density of the SSC device reaches as high as 20.13 W h kg –1 , whereas that of ASC approaches 87.5 W h kg –1 .