ISSN 0036ꢀ0236, Russian Journal of Inorganic Chemistry, 2012, Vol. 57, No. 2, pp. 160–162. © Pleiades Publishing, Ltd., 2012.
Original Russian Text © N.A. Mamedova, S.S. Ragimov, F.M. Sadykhov, I.I. Aliev, 2012, published in Zhurnal Neorganicheskoi Khimii, 2012, Vol. 57, No. 2, pp. 201–203.
SYNTHESIS AND PROPERTIES
OF INORGANIC COMPOUNDS
Preparation and Physicochemical Study of Nickel(II)
Thiostannate in the NiCl2–SnS2–H2O System
N. A. Mamedova, S. S. Ragimov, F. M. Sadykhov, and I. I. Aliev
Nagiev Institute of Chemical Problems, National Academy of Sciences of Azerbaijan, Baku, Azerbaijan
eꢀmail: itpcht@itpcht.ab.az
Received September 4, 2009
Abstract—Nickel(II) thiostannate is prepared in the NiCl2–SnS2–H2O system by precipitation from soluꢀ
tions. Its formation temperature and homogenization time are determined. The synthesis of NiSnS3 from the
ammonium acetate buffer solution is found to last 6–8 h at 80–90°C. The elemental composition of ternary
nickel(II) thiostannate is detrermined by chemical analysis.
DOI: 10.1134/S0036023612020179
It has been known that thiostannates of various for 6–8 h, yielding NiSnS3. This compound was
metals are generally prepared by a direct ampoule annealed at 600
°
С for 350 h to achieve homogenizaꢀ
technique [1–3]; however, they can also be prepared tion; the elemental analysis was then carried out.
indirectly by precipitation from solutions.
NiSnS3 compound was also studied using the
methods of physicochemical analysis (DTA, XRD,
MS analysis, density and microhardness measureꢀ
ments).
This method is typically used to prepare comꢀ
pounds with high melting temperatures and hardꢀtoꢀ
get peritectic compounds.
This method can be used to prepare compounds
such as МSnX2, M2SnX3, and MSnS3 at lower temperꢀ
atures and pressures. With this purpose, chalcogen
acids are used to act upon the corresponding solutions
of salts of this metal. Chalcogen compounds prepared
by precipitation from solutions are more homogeꢀ
neous compared to the compounds prepared using the
ampoule method. However, the drawback of the preꢀ
cipitation method is that the synthesis involves several
operations, during which the resulting products are
contaminated with impurities.
Differential thermal analysis of the compound was
carried out on an NTRꢀ73 lowꢀfrequency thermal
recorder with a Pt/Pt–Rh thermocouple. The heating
rate was 10 K/min.
Powder Xꢀray diffraction was measured on a
DRONꢀ3 diffractometer (Cu
K radiation, Ni filter).
α
Microstructure examination of the polished etched
slices (with KOH : Н2О2 = 1 : 1 used as an etching
agent) was performed on an MIMꢀ8 microscope.
Microhardness was measured on a PMTꢀ3 microꢀ
hardness tester under a load of 20 g. The density of
NiSnS3 was determined pycnometrically; toluene was
used as a filling agent.
We have earlier obtained thiostannates of various
metals (Cu, Ni, Co, etc.) [4–6].
Alloys of composition A1 BIVCVI (А1 = Cu, BIV =
Ge, Sn, Pb; CVI = S, Se, Te2) have been synthesized.
Thiostannates Tl4SnS4, TlSnS2, Cu2SnS3, and
CdSnS3 have been prepared using a hydrothermal
method. It has been ascertained that most metal sulꢀ
fides interact with tin(IV) sulfide in acidic medium to
yield stable thio compounds. Numerous thio comꢀ
pounds can be obtained by varying the composition of
components [7].
RESULTS AND DISCUSSION
In order to obtain SnS2
,
SnCl2 2H2O was dissolved
⋅
in water with addition of concentrated hydrochloric
acid and hydrogen peroxide, followed by heating. The
resulting SnCl4 solution was diluted, and H2S was then
passed through the resulting solution. The SnS2 preꢀ
cipitate was washed until sulfide ions were completely
removed and was then converted into a soluble form.
An equivalent amount of NiCl2 was added to SnS2 colꢀ
loidal solution at pH 3.0–3.8:
The results of the synthesis of nickel(II) thiostanꢀ
nate NiSnS3 from aqueous solution in the NiCl2–
SnS2–H2O system are presented in this study.
2NiCl2 + 3SnS2
→
2NiSnS3 + SnCl4.
EXPERIMENTAL
Optimal conditions for producing nickel(II)
NiCl2 and SnS2 solutions were used to produce thiostannate in the NiCl2–SnS2–H2O system were
nickel(II) thiostannate. The reaction was carried out selected based on experimental data. Ammonium aceꢀ
in an ammonium acetate buffer solution at 80–90
°
С
tate buffer (CH3COONH4 + NH4OH) was added to
160