Ion‐exchange synthesis of microporous Co ₃ S ₄ for enhanced electrochemical energy storage

Abstract

Replacing oxygen in an oxide-based material with sulfur can produce improved flexibility and more efficient electron transport in its structure leading to enhanced electrical performance. Herein, facile template-free growth of free-standing cobalt (II, III) oxide (Co 3 O 4 ) on Ni foam via a mild hydrothermal technique followed by its transformation to cobalt (II, III) sulfide (Co 3 S 4 ) via an ion-exchange is reported. The microstructural morphology, phase, and porosity of the prepared Co 3 O 4 and Co 3 S 4 are characterized by FESEM, XRD, Raman, XPS, TEM, and BET analyses. The electrochemical performance of the Co 3 S 4 film with a microporous morphology is considerably superior to that of Co 3 O 4 , exhibiting a high specific capacitance of 1604 F g À1 (905 F g À1 for Co 3 O 4 ), the excellent restorative ability of $99% at 1 A g À1 ($96% for Co 3 O 4 ), and

Hollow Ni3S4@Co3S4 with core–satellite nanostructure derived from metal–organic framework (MOF)-on-MOF hybrids as an electrode material for supercapacitors

“…The reaction mechanism of the Ni 3 S 4 @Co 3 S 4 electrode is as follows. 48,49 Ni 3 S 4 + OH − ⇌ Ni 3 S 4 (OH) + e − Ni 3 S 4 (OH) + OH − ⇌ Ni 3 S 4 O + H 2 O + e − Co 3 S 4 + OH − ⇌ Co 3 S 4 (OH) + e − Co 3 S 4 (OH) + OH − ⇌ Co 3 S 4 O + H 2 O + e − …”

The surface-sulphurated Co3O4 nanowire array electrocatalyst for oxygen evolution reaction and water-splitting applications

“…3f, the asymmetric peaks at 163.5 eV and 162.1 eV are assigned to S 2p 1/2 and S 2p 3/2 , respectively. 34 The peak at 166.0 eV is also characteristic of the typical metal–sulphur bond (M–S). 43 This indicates that the metal does react with sulphur during surface vulcanization, which is also consistent with the results of the Co 2p spectrum.…”

Cu2O/Co3O4nanoarrays for rapid quantitative analysis of hydrogen sulfide in blood

“…7(a), with a binding energy of 163.3 and 164.4 eV corresponding to Cu 2 S 48,49 and Co 3 S 4 (ref. 50 and 51) respectively. The peak at 168.1 eV can be assigned to sulfates (SO 4 2− , SO 3 2− , and S 2 O 3 2− ), 48,52 which are formed because of oxidation reactions caused by the high potential between sulfides and O 2 .…”