Electrodeposited cobalt-based electrocatalysts for efficient oxygen evolution reaction and supercapacitors

Abstract

Although transition metal oxides/hydroxides have gone through many modifications including heteroatoms doping to improve their performance towards electrocatalytic water splitting and supercapacitors, their superior performance is yet to come. Herein, cobalt hydroxide was calcined, sulfurized, and phosphorized, which was prepared via a facile electrodeposition process on nickel foam at −1.0 V. Based on the experimental results, the cobalt sulfide showed a lower overpotential of 282 mV to achieve a current density of 10 mA/cm2 for oxygen evolution process. Moreover, the prepared optimized cobalt sulfide sample displayed the highest specific capacitance of 3.7 F/cm2 along with the largest energy density (0.144 Wh/cm2) as well as high power density (8.28 W/cm2). The prepared optimized cobalt sulfide sample showed a very stable electrochemical performance suggesting that the facile electrodeposition process can produce efficient electrocatalysts for the oxygen evolution process.

Keywords

• Electrochemical deposition
• Electrocatalysts
• Cobalt oxide
• Cobalt sulfide