NiCo2S4-Based Materials for Electrochemical Applications

Abstract

NiCo2S4 has attracted worldwide attention in the field of energy storage/conversion. In this paper, we summarize the up-to-date progress on the preparation strategies, the applications as electrode materials for supercapacitors, lithium-ion batteries and dye sensitized solar cells, as well as electrocatalysts for the hydrogen evolution reaction, oxygen reduction reaction and oxygen evolution reaction. We also discuss the strategies to improve the electrochemical performance, and future trends of the NiCo2S4-based materials.

Bifunctionally active nanosized spinel cobalt nickel sulfides for sustainable secondary zinc–air batteries: examining the effects of compositional tuning on OER and ORR activity

“…89 Additionally, NiCo 2 S 4 is more flexible in structure due to the lower electronegativity of sulfur, allowing for reversible layer elongation and contraction within the intact structure which facilitates good electron transport. 18,84,90 Suntivich et al correlated the catalytic activities of spinel metal oxides to the e g -orbital occupancy in the electronic structure of the metal cations at low-spin octahedral centres, which has also been found to hold true for spinel metal oxides. 91,92 Spinel materials with an e g -orbital occupancy level of close to unity were found to favour electron transfer from the surface metal cations to the adsorbed intermediates.…”

“…5,9 For instance, cobalt nickel chalcogenide spinels exhibited notably improved activities over their individual monometallic counterparts in the catalysis of methane oxidation or water oxidation. 18,19 Spinel bimetallic sulfides (e.g. NiCo 2 S 4 ) are also of interest for oxygen electrocatalysis, thanks to their rich multivalent oxidation state chemistry, good chemical and thermal stability, high electronic conductivity, and rich exposed octahedral active sites.…”

“…NiCo 2 S 4 ) are also of interest for oxygen electrocatalysis, thanks to their rich multivalent oxidation state chemistry, good chemical and thermal stability, high electronic conductivity, and rich exposed octahedral active sites. 7,18,20,21 NiCo 2 S 4 can be synthesized in various morphologies and has been used in other applications such as an active material in supercapacitors, lithium-ion batteries, dye-sensitized solar batteries, and catalysis including the ORR, OER and hydrogen evolution reaction (HER). [22][23][24][25][26][27] These NiCo 2 S 4 nanostructures, such as spheres and wires, have all exhibited good bifunctional OER and ORR activity, 5,6,8,9,12,[28][29][30] which may be further enhanced by improving electron transfer via the engineering of surface morphology, incorporating highly conductive support materials, and doping with selected tertiary atoms.…”

“…5,[31][32][33][34][35][36][37] Previous studies show that NiCo 2 S 4 possesses a mixedvalence redox chemistry. 5,12,18 However, it remains largely not understood how individual cobalt and nickel cations affect the electrocatalytic performance of NiCo 2 S 4 . 12,17 The intrinsic filling restrictions of the spinel structure, fortunately, allow the contribution of each cationic species with specific occupancy in the bimetallic spinels to be distinguished and correlated to the catalytic activities.…”

Enhancing bifunctional catalytic activity of cobalt–nickel sulfide spinel nanocatalysts through transition metal doping and its application in secondary zinc–air batteries

“…5,9 For instance, as compared to their monometallic counterparts, the coupling of cobalt with nickel in their bimetallic chalcogenide spinels resulted in the improved catalytic activities during methane and water oxidation. 19,20 Spinel bimetallic suldes (e.g., NiCo 2 S 4 ) are of interest in oxygen electrocatalysis due to their rich multivalent oxidation state chemistry, good thermal and mechanical stability, exceptional electronic conductivity, large population of exposed octahedral catalytically active sites, as well as a favourable electronic structure. 7,19,21,22 NiCo 2 S 4 has been synthesized and evaluated in various morphologies in Li-ion batteries, supercapacitors, dye-sensitized solar cells, and as OER, ORR, and Hydrogen Evolution Reaction (HER) catalysts.…”