Hierarchical CuCo₂S₄ Nanoflake Arrays Grown on Carbon Cloth: A Remarkable Bifunctional Electrocatalyst for Overall Water Splitting

Abstract

Fabricating self-supporting electrocatalysts with double functions for overall water splitting is a promising strategy for clean energy generation. Herein, spinel-based CuCo 2 S 4 nanoflakes were grown vertically on carbon cloth (CC) substrate to obtain hierarchical self-supporting CuCo 2 S 4 /CC electrocatalysts through a hydrothermal process. The influence of hydrothermal time on the surface morphology and electrocatalytic properties of the CuCo 2 S 4 /CC was investigated. The rational synthetic approach can significantly reduce the diffusion path and promote the transfer of charge. As a result, the optimized CuCo 2 S 4 /CC exhibits a significantly higher electrocatalytic activity than the control single metal sulfide catalysts (CoS 1.097 /CC and CuS/CC) in 1.0 M KOH solution, and relatively overpotentials of 204 and 280 mV are demanded to generate a current density of 10 mA cm À 2 for hydrogen evolution reaction and oxygen evolution reaction, respectively. The significantly enhanced electrocatalytic activity benefits from the synergetic effect of the fast charge transport and abundant catalytic active sites. Moreover, in an overall water splitting system, a two-electrode setup constructed using CuCo 2 S 4 /CC as both cathode and anode shows a low voltage of 1.58 V at 10 mA cm À 2 and high durability. This study provides a rational strategy for improving the overall water splitting performance by constructing selfsupporting spinel-based catalysts.

Djurleite Copper Sulfide-Coupled Cobalt Sulfide Interface for a Stable and Efficient Electrocatalyst

“…The CoS 2 -decorated CuS nanoparticles exhibit excellent electrochemical performance compared with pure CoS 2 and CuS . Overall, cobalt-coated copper sulfide materials are expected to exhibit higher catalytic performance for the OER. − …”

Hydrothermal construction of flower‐like CuS microsphere electrocatalysts for hydrogen evolution reactions in alkaline fresh water, alkaline seawater, and seawater

“…Recently, the increase in fossil fuel depletion with environmental pollution has urged researchers to find out alternative renewable energy resources such as hydrogen fuel. 1 Hydrogen is found to be an attractive fuel, which has been produced with zero percentage carbon emission. 2 A number of techniques such as electrochemical, photoelectrochemical, and photocatalytic water splitting have been employed to produce hydrogen either in fresh or seawater.…”

“…Recently, the increase in fossil fuel depletion with environmental pollution has urged researchers to find out alternative renewable energy resources such as hydrogen fuel 1 . Hydrogen is found to be an attractive fuel, which has been produced with zero percentage carbon emission 2 .…”

Three‐Dimensional Porous MnCo2S4 Microrugby Balls Supported on Carbon Cloth for Efficient Oxygen Evolution Reaction

“…Bitransition metal sulphide has a variety of metal oxidation states, a more flexible structure and higher conductivity than their corresponding oxides because of the relatively weak M−S bonds via replacing oxygen with sulfur [11] . Accordingly, it has been recognized that bitransition metal sulphides (MnCo 2 S 4 , [12] NiCo 2 S 4 , [13] CuCo 2 S 4 , [14] and FeCo 2 S 4 , [15] NiIn 2 S 4 , [16] etc.) have good electrocatalytic performance, which are due to the synergistic effect caused by electronic regulation between metals.…”