3D Hierarchically Mesoporous Zinc-Nickel-Cobalt Ternary Oxide (Zn0.6Ni0.8Co1.6O4) Nanowires for High-Performance Asymmetric Supercapacitors

Muhammad Tayyab Ahsan; Muhammad Usman; Zeeshan Ali; Sofia Javed; Rashad Ali; Muhammad U Farooq; Muhammad Aftab Akram; Asif Mahmood

doi:10.3389/fchem.2020.00487

3D Hierarchically Mesoporous Zinc-Nickel-Cobalt Ternary Oxide (Zn_0.6Ni_0.8Co_1.6O₄) Nanowires for High-Performance Asymmetric Supercapacitors

Front Chem. 2020 Jun 15:8:487. doi: 10.3389/fchem.2020.00487. eCollection 2020.

Authors

Muhammad Tayyab Ahsan^{1

2}, Muhammad Usman¹, Zeeshan Ali¹, Sofia Javed¹, Rashad Ali³, Muhammad U Farooq⁴, Muhammad Aftab Akram¹, Asif Mahmood⁵

Affiliations

¹ School of Chemical & Materials Engineering, National University of Sciences and Technology (NUST), Islamabad, Pakistan.
² Department of Materials Science and Engineering, College of Engineering, Peking University, Beijing, China.
³ School of Materials and Energy, University of Electronic Science and Technology of China, Chengdu, China.
⁴ Department of Physics, University of Education, Faisalabad Campus, Faisalabad, Pakistan.
⁵ School of Chemical and Biomolecular Engineering, The University of Sydney, Sydney, NSW, Australia.

Abstract

Increased efforts have been devoted recently to develop high-energy-density supercapacitors (SC) without renouncing their power efficiency. Herein, a hierarchically mesoporous nanostructure of zinc-nickel-cobalt oxide (ZNCO) nanowires (NWs) is constructed by hierarchical aggregation of ZNCO nanoparticles. It is worth noting that cobalt and nickel rich lattice imparts higher charge storage capability by enhanced reversible Faradaic reaction while zinc provides structural stability and higher conductivity. Moreover, particulate nature of ZNCO NWs allows deep diffusion of electrolyte thus enabling reversible charge storage under higher current densities. The as-prepared ZNCO NWs exhibited excellent specific capacitance of 2082.21 F g^-1 at the current density of 1 A g^-1 with high stability up to 5,000 charge-discharge cycles. Further, the asymmetric SC device was assembled using ZNCO NWs (ZNCO NWs//MWCNTs) which exhibited high energy density of 37.89 Wh kg^-1 and excellent capacitance retention up to 88.5% over 1,000 cycles. This work presents ways to construct multi-component high-energy-density materials for next-generation energy storage devices.

Keywords: SCs; aqueous asymmetric supercapacitors; hierarchically porous nanostructures; high energy density; zinc-nickel-cobalt oxide.