The Formation Process of Cobalt Sulfide from Tricobalt Tetraoxide Using Sulfur Dioxide as a Sulfidizing Agent

Abstract

The products obtained by heating a mixture of Co3O4 and carbon in a SO2 stream were CoO and CoSO4 at 400–600 °C, Co1−xS and CoO at 650–700 °C, and Co1−xS (Co0.90S) at 750–800 °C. Sulfur was obtained outside the heating zone throughout the temperature range. The possible reactions during the above process were also examined. Further, thermodynamical consideration was made of the formation of Co1−xS. The formation process of Co1−xS (Co0.90S) from Co3O4 can be represented as follows: The reaction of carbon with SO2 occurs at first to form sulfur. Above ca. 400 °C, the reaction of Co3O4 with SO2 occurs to form CoO and CoSO4. Above ca. 500 °C, the reductions of Co3O4 with carbon and with sulfur also occur to form CoO. Above ca. 600 °C, the reduction of Co3O4 with carbon occurs to form CoO. Above ca. 650 °C, Co1−xS is formed by the reaction of CoO with sulfur, both of which had been formed by the above reactions.

Synthesis and characterization of nanosize cobalt sulfide for rechargeable lithium batteries

“…For example, cobalt sulfide could be formed by the reaction of cobalt with sulfur [6] or hydrogen sulfide [7] or by reaction of cobalt monoxide with hydrogen sulfide [8]. Cobalt sulfide has also been synthesized by the reaction of Co 3 O 4 with SO 2 in the presence of carbon [9]. With these methods, high-temperature (600-800 • C) quenching was needed to form crystalline cobalt sulfide [10].…”

High-Pressure Synthesis, Crystal Structure, and Physical Properties of a Spinel Compound Co0.7Al2S4

“…The powder X-ray diffraction (PXRD) of the sample was measured and is plotted in Figure . The result shows that the main diffraction peaks can be indexed using a cubic spinel structure like FeAl 2 S 4 , but an obvious impurity phase of Co 1– x S is included, which is denoted by the green asterisks also as shown in Figure . Then, we tried to decrease the content of Co and carried out the synthesis to prepare the pure compound, of which the details are the same as the above.…”

Hydrazine-Assisted Low-Temperature Hydrothermal Preparation of Nanocrystalline Jaipurite

“…For example, cobalt sul"de could be formed by the reaction of cobalt with sulfur (3) or hydrogen sul"de (4) or by the reaction of cobalt monoxide (CoO) with hydrogen sul"de (5). There have also been reports regarding the synthesis of cobalt sul"de by the reaction of Co O with SO in the presence of carbon (6). With these methods, high-temperature quenching (600} 8003C) was needed to form crystalline cobalt monosul"de (6,7).…”

“…There have also been reports regarding the synthesis of cobalt sul"de by the reaction of Co O with SO in the presence of carbon (6). With these methods, high-temperature quenching (600} 8003C) was needed to form crystalline cobalt monosul"de (6,7). As we know, the low-temperature chemical solution route has seldom been reported to be used to prepare crystalline cobalt monosul"de.…”