Jump to main content
Jump to site search
Access to RSC content Close the message box

Continue to access RSC content when you are not at your institution. Follow our step-by-step guide.


Issue 15, 2020
Previous Article Next Article

Comparative electrochemical energy storage performance of cobalt sulfide and cobalt oxide nanosheets: experimental and theoretical insights from density functional theory simulations

Author affiliations

Abstract

In this study, we have carried out studies on supercapacitor performance comparing cobalt oxide (Co3O4) with cobalt sulfide (Co3S4) nanosheets grown using a facile electrodeposition approach. We have investigated the origin of enhanced energy storage performance of Co3S4 as compared to Co3O4 both by supported experiments and density functional theory investigations. Cobalt oxide exhibits a specific capacitance of 200 F g−1 at a current density of 2 A g−1, whereas a high specific capacitance of 558 F g−1 was achieved in the case of the Co3S4 nanosheets. The enhanced supercapacitor performance of Co3S4 is due to the high surface area, better wettability and high conductivity of the nanosheets. The asymmetric device exhibited a maximum energy density of 47.3 W h kg−1 with a power density of 2388.4 W kg−1 for Co3S4//MWCNT. The electrochemical impedance spectroscopic analysis revealed that Co3O4 has a substantially bigger semicircle as compared to Co3S4, confirming inferior charge-transfer characteristics in Co3O4. Density functional theory (DFT) simulations revealed that bulk structures of both Co3S4 and Co3O4 have an anti-ferromagnetic (AFM) configuration with Co atoms at the tetrahedral site having an opposite spin (∼2.55 μB each) and those at the octahedral sites being non-magnetic. Co3S4 nanosheets are found to be more conducting due to the presence of higher density of states near the Fermi level and a smaller bandgap compared to Co3O4 which support the observed experimental data on enhanced energy storage performance of Co3S4.

Graphical abstract: Comparative electrochemical energy storage performance of cobalt sulfide and cobalt oxide nanosheets: experimental and theoretical insights from density functional theory simulations

Back to tab navigation

Supplementary files

Article information


Submitted
28 Nov 2019
Accepted
25 Feb 2020
First published
26 Feb 2020

Phys. Chem. Chem. Phys., 2020,22, 7903-7911
Article type
Paper

Comparative electrochemical energy storage performance of cobalt sulfide and cobalt oxide nanosheets: experimental and theoretical insights from density functional theory simulations

R. Samal, S. Mondal, A. S. Gangan, B. Chakraborty and C. S. Rout, Phys. Chem. Chem. Phys., 2020, 22, 7903
DOI: 10.1039/C9CP06434F

Social activity

Search articles by author

Spotlight

Advertisements