Homogeneous Elongation of N-Doped CNTs over Nano-Fibrillated Hollow-Carbon-Nanofiber: Mass and Charge Balance in Asymmetric Supercapacitors Is No Longer Problematic

Taewoo Kim; Subhangi Subedi; Bipeen Dahal; Kisan Chhetri; Tanka Mukhiya; Alagan Muthurasu; Jagadis Gautam; Prakash Chandra Lohani; Debendra Acharya; Ishwor Pathak; Su-Hyeong Chae; Tae Hoon Ko; Hak Yong Kim

doi:10.1002/advs.202200650

Homogeneous Elongation of N-Doped CNTs over Nano-Fibrillated Hollow-Carbon-Nanofiber: Mass and Charge Balance in Asymmetric Supercapacitors Is No Longer Problematic

Adv Sci (Weinh). 2022 Jul;9(20):e2200650. doi: 10.1002/advs.202200650. Epub 2022 May 14.

Authors

Taewoo Kim¹, Subhangi Subedi^{1

2}, Bipeen Dahal^{1

3}, Kisan Chhetri¹, Tanka Mukhiya^{1

4}, Alagan Muthurasu¹, Jagadis Gautam⁵, Prakash Chandra Lohani^{1

6}, Debendra Acharya¹, Ishwor Pathak^{1

6}, Su-Hyeong Chae¹, Tae Hoon Ko¹, Hak Yong Kim^{1

7}

Affiliations

¹ Department of Nano Convergence Engineering, Jeonbuk National University, Jeonju, 54896, Republic of Korea.
² Department of Chemistry, Trichandra Multiple Campus, Tribhuvan University, Kathmandu, 44605, Nepal.
³ Central Department of Chemistry, Tribhuvan University, Kathmandu, 44618, Nepal.
⁴ Department of Chemistry, Bhaktapur Multiple Campus, Tribhuvan University, Kathmandu, 44800, Nepal.
⁵ School of Materials Science and Engineering, Kumoh National Institute of Technology, 61 Daehak-ro, Gumi-si, Gyeongsangbuk-do, 39177, Republic of Korea.
⁶ Department of Chemistry, Amrit Campus, Tribhuvan University, Kathmandu, 44600, Nepal.
⁷ Department of Organic Materials and Fiber Engineering, Jeonnbuk National University, Jeonju, 561-756, Republic of Korea.

Abstract

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 .

Keywords: N-doped carbon nanotubes (CNTs); double layer anodes; electrospinning; mass balancing; metal-organic frameworks; nano-fibrillated hollow carbon nanofibers (CNFs); supercapacitors.

Abstract

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