Hydrazine-controlled hydrothermal synthesis of Co₉S₈ from a homogeneous solution

Abstract

Single-phase nanocrystalline Co9S8 was prepared by hydrothermal treatment of Co(Ac)2 and NH2CSNH2 in hydrazine solution at 170 °C. The products were characterized by x-ray powder diffraction (XRD) technique, transmission electron microscope (TEM), and wet chemical analysis. XRD indicated the product was the cubic Co9S8 phase. The relative crystallite size was 6.3 nm as determined by the Scherrer method. TEM images showed the particles were agglomerative. The electron diffraction pattern also revealed their nanocrystalline nature. In this hydrothermal formation process of Co9S8, hydrazine was a critical factor. The formation process is discussed.

Liquid phase chemical synthesis of Co–S microspheres with novel structure and their electrochemical properties

“…Conventionally, cobalt sulfide powders were prepared by traditional solid state method [14], but the high temperature could lead to a large particle size and an inhomogeneity. Recently, extensive attention has been focused on the hydrothermal and solvothermal synthesis of transition metal sulfides powders [15,16], largely because the reaction can proceed at a mild temperature, and the size, morphology, and phase homogeneity of the production can be well controlled. However, most of the previous work reported is about Co 9 S 8 and CoS 2 phases of cobalt sulfides, * Corresponding author.…”

D-tracer study of butadiene hydrogenation and tetrahydrothiophen hydrodesulphurisation catalysed by Co9S8

“…In the case of molybdenum sulphide catalysis, we obtained useful information by use of bulk material [18,19], and correspondingly in this investigation of Co 9 S 8 the catalyst has been in the form of an unsupported powder. Many novel techniques for the preparation of bulk Co 9 S 8 have recently been described [12,[20][21][22][23][24]; however, the traditional route involving the sulphidation of Co 3 O 4 was used in this investigation.…”

Solvothermal Synthesis of Non‐Oxide Nanomaterials

“…By hydrothermal polymerization and simultaneous sulfidation processes, nanocomposites CdS/poly(vinyl acetate) nanorods [12] and nanospheres [13] were synthesized. In aqueous hydrazine solutions, nonstoichiometric metal telluride nanocrystallites such as Cu 2:86 Te 2 , Cu 7 Te 5 , Cu 2Àx Te, and Ag 7 Te 4 [14], and cubic Co 9 S 8 were hydrothermally synthesized [15]. Other transition metal chalcogenides, such as single-molecular-layer MoS 2 [16] and MoSe 2 [17] were also prepared under hydrothermal conditions.…”

“…15. TEM (a) and (b) and HRTEM image (c) of the multiwall carbon nanotubes prepared by a catalytic-assembly solvothermal route.…”