Synthesis and study of ammonium hexamolybdobismuthate(III)

Article abstract of DOI:10.1134/S0036023611120412

Ammonium hexamolybdobismuthate(III) of composition (NH₄) ₃[BiMo₆O₁₈(OH)₆] · 7H ₂O (I) was synthesized and studied by mass spectrometry, X-ray diffraction, IR spectroscopy, and thermogravimetry. The compound is monoclinic: a = 10.438 A?, b = 7.909 A?, c = 18.127 A?, β = 96.59°, V = 1486.76 A?³, ρ_calc = 3.32 g/cm³, Z = 2. Pleiades Publishing, Ltd., 2011.

Full text of DOI:10.1134/S0036023611120412

ISSN 0036ꢀ0236, Russian Journal of Inorganic Chemistry, 2011, Vol. 56, No. 12, pp. 1883–1885. © Pleiades Publishing, Ltd., 2011.
Original Russian Text © A.V. Oreshkina, G.Z. Kaziev, N.N. Lobanov, A.V. Steblevskii, 2011, published in Zhurnal Neorganicheskoi Khimii, 2011, Vol. 56, No. 12, pp. 1971–1973.
SYNTHESIS AND PROPERTIES
OF INORGANIC COMPOUNDS
Synthesis and Study of Ammonium Hexamolybdobismuthate(III)
A. V. Oreshkinaa, G. Z. Kazieva, N. N. Lobanovb, and A. V. Steblevskiic
a Moscow State Pedagogical University, Malaya Pirogovskaya ul. 1, Moscow, 119882 Russia
b Russian University of Peoples’ Friendship, ul. MiklukhoꢀMaklaya 6, Moscow, 117198 Russia
c Kurnakov Institute of General and Inorganic Chemistry, Russian Academy of Sciences,
Leninskii pr. 31, Moscow, 119991 Russia
Received June 30, 2010
Abstract—Ammonium hexamolybdobismuthate(III) of composition (NH4)3[BiMo6O18(OH)6]
was synthesized and studied by mass spectrometry, Xꢀray diffraction, IR spectroscopy, and thermogravimetry.
The compound is monoclinic: = 10.438 = 7.909 = 18.127 = 96.59
= 1486.76 Å3, ρcalc
3.32 g/cm3,
= 2.
⋅
7H2O (I)
a
Å,
b
Å,
c
Å,
β
°
,
V
=
Z
DOI: 10.1134/S0036023611120412
Heteropoly compounds (HPCs) are complex comꢀ
For (NH4)3[BiMo6O18(OH)6] · 7H2O calcd. (wt %):
pounds with a unique structure, acid–base and oxidaꢀ Bi, 15.42; N, 3.96; Mo, 42.55; O, 30.04; H2O, 9.31.
tion–reduction properties [1]. In the midꢀ20th cenꢀ
tury, Perloff performed an Xꢀray diffraction study of
the structure of sodium hexamolybdochromate
octahydrate and proved that the united ligand is repreꢀ
sented by a torus consisting of six MoO6 octahedra
joined by vertices, faces, or edges [2]. The detailed
description of the structure of HPCs was given in [3,
4]. HPCs are applied in various fields of science and
technology, in medicine and photochemistry, analytiꢀ
cal chemistry and chemical engineering [1, 5], as catꢀ
alysts in the organic synthesis reactions [6–9]. Ammoꢀ
nium hexamolybdometallates have been recently preꢀ
pared [10–14].
Found (wt %): Bi, 15.44; N, 3.98; Mo, 42.51; O,
28.34; H2O, 9.29.
Xꢀray diffraction analysis was carried out on a
DRONꢀ7 automated diffractometer (Cu
K radiation,
α
graphite monochromator); silicon was used as an
external standard. Samples were preliminarily ground
in a jasper mortar. XRD patterns were processed in two
stages. At the first stage, peak maximum positions and
integrated intensities determined using the DrWin
program of the PDWin software was refined. At the
second stage, XRD patterns were indexed using the
Ind autoindexing program of the same software.
Phases were identified using a of the JCPDS Powder
Data File (2011 version).
This work was devoted to synthesizing ammonium
hexamolybdobismuthate(III)
(NH4)3[BiMo6O18(OH)6] 7H2O and studying it by
mass spectrometry, Xꢀray diffraction, IR spectroscopy,
and thermogravimetry.
of
composition
The IR spectrum of the compound was recorded on
a PerkinꢀElmer spectrophotometer within the 200–
4000 cm–1 frequency range. The samples were preꢀ
pared as KBr pellets.
⋅
TGA was carried out using a PaulikꢀErdeyꢀPaulik
Qꢀ1500 instrument over the temperature range of 20–
1000 С; the heating rate was 10 K/min; sample weight
EXPERIMENTAL
°
was 10 mg. Calcined alumina was used as a reference.
Ammonium hexamolybdobismuthate was preꢀ
pared using a modification of the procedure described
in [1]. The solution of bismuth (III) nitrate was added
to a saturated solution of ammonium paramolybdate
acidified with nitric acid to pH 3. The resulting mixꢀ
ture was heated on a water bath for several hours folꢀ
lowed by cooling in an desiccator. Several days after,
light yellow crystals (NH4)3[BiMo6O18(OH)6] 7H2O
precipitated; they were filtered and recrystallized sevꢀ
eral times.
RESULTS AND DISCUSSION
Xꢀray diffraction analysis was carried out to corꢀ
roborate the individuality and purity of the syntheꢀ
sized compound and to obtain crystallographic data
(Fig. 1, table). The comparison of the XRD patterns
with the PCPDFWIN database demonstrated that the
compound is individual, contains no possible impuriꢀ
ties, and belongs to the monoclinic crystal system with
⋅
Mass spectrometry analysis was carried out to the following unit cell parameters:
determine the quantitative and qualitative analysis of 7.909 = 18.127 = 96.59
= 1486.76 Å3. The
the compound: pycnometric density was determined by the Syromyatꢀ
a = 10.438, b =
Å,
c
Å,
β
°, V
1883

1884
, %
ORESHKINA et al.
I
I
100
90
80
70
60
50
40
30
20
10
0
385
650
1600
1400
940
3380
905
3500
2000 1500 1000 500 100
, cm–1
ν
5
10
15
20
25
30
, deg
2θ
Fig.
1.
Line
diffraction
pattern
of
Fig. 2. IR spectrum of (NH ) [BiMo O (OH) ] · 7H O
.
(NH ) [BiMo O (OH) ] · 7H O
.
4 3
6
18
6
2
4 3
6
18
6
2
nikov procedure [15] and is ρcalc = 3.32 g/cm3. The in the form of a doublet within the 905–940 cm–1 range
number of formula units was calculated: = 2. corresponds to the asymmetric and symmetric stretchꢀ
ing oscillations of terminal cis МоО2 groups; the bands
νs νas)
at 560 cm–1 and a strong band at 650 cm–1
Z
ꢀ
The comparison of the IR spectrum of the syntheꢀ
sized compound and previously studied HPCs [16]
points to their identity, which enables one to perform
band assignment (Fig. 2).
(
)
(
belong to the symmetric and asymmetric stretching
oscillations of the Mo–O fragment:
H
Mo
The fundamental vibrations of terminal cisꢀМоО2
groups and bridge Mo–O–Mo groups manifest themꢀ
O Bi
Mo
selves within the 200–1000 cm–1 range. An intense band
There is no strongly pronounced band correspondꢀ
ing to the vibrations of the Bi–O bond because of band
superposition in the spectra. The bands below 400 cm–1
are caused by the bending vibrations of both cisꢀMoꢀO2
groups and bridge Mo–O–Mo bonds.
The intense bands at 1400 and 1600 cm–1, which
are likely to belong to the vibrations in NH3 groups,
are observed in the IR spectrum. In addition to these
bands, there are bands at 3380 cm–1, belonging to the
vibrations of water and hydroxide groups.
XRD data for the compound (NH4)3[BiMo6O18(OH)6]
7H2O
⋅
2
θ
, deg
d,
Å
I
, %
h
k
l
9.35
9.85
9.45
8.96
8.54
7.22
6.28
6.05
5.80
4.77
4.50
4.12
3.90
3.85
3.78
3.69
3.62
51
80
14
100
35
41
31
26
12
15
11
23
24
22
21
1
0
1
2
1
1
0
1
1
3
4
1
4
0
2
0
2
0
–1
0
0
0
1
1
1
1
1
0
1
1
2
2
2
2
10.34
12.24
14.09
14.60
15.25
18.57
19.72
21.50
22.74
23.01
23.48
24.04
24.57
The TGA of (NH4)3[BiMo6O18(OH)6]
⋅
7H2O
showed the presence of two endoterms and one exoꢀ
therm (Fig. 3).
1
The first endotherm in the range near 90°С and the
second endotherm at 125 correspond to the stepꢀ
°С
1
wise removal of five and two molecules of crystal
hydrate water, respectively. Three ammonia molecules
and 4.5 molecules of constitution water are released
–1
0
with an exotherm (at 380°С). The third endotherm at
770 corresponds to removal of six molybdenum
°С
0
oxide molecules.
The thermal decomposition scheme appears as folꢀ
lows:
–2
0
−5H2O
90°C
−2H2O
⎯⎯⎯⎯⎯→
125°C
1
(NH4)3[BiMo6O18(OH)6]
(NH4)3[BiMo6O18(OH)6] 2H O
2
· 7H O
⎯⎯⎯⎯⎯→
2
0
→
⋅
1
−3NH3,−4.5H2O
→
(NH ) [BiMo O (OH) ]
4 3 6 18 6
⎯⎯⎯⎯⎯⎯⎯⎯→
0
380 C
°
RUSSIAN JOURNAL OF INORGANIC CHEMISTRY Vol. 56 No. 12 2011

SYNTHESIS AND STUDY
1885
2. A. Perloff, Inorg. Chem. 9 (10), 2228 (1970).
3. V. S. Sergienko and M. A. PoraiꢀKoshits, Itogi Nauki
Tekh., Ser. Kristallokhimiya 19, 79 (1985).
4. M. A. PoraiꢀKoshits and L. O. Atovmyan, Itogi Nauki
Tekh., Ser. Kristallokhimiya 19, 3 (1985).
5. D. B. Dubovik, T. I. Tikhomirova, A. V. Ivanov, et al.,
Δ
m
, %
T, °C
TG
900
700
500
300
100
770
10
20
30
TGA
380
J. Anal. Chem. 58 (9), 802 (2003).
125
90
6. K. I. Matveev and I. V. Kozhevnikov, Kinet. Katal. 21
(5), 1189 (1980).
Т
7. M. Misono, Catalysis by Acids and Bases (Elsevier,
Amsterdam, 1985), Vol. 20, p. 445.
8. G. M. Maksimov, Usp. Khim. 64 (5), 480 (1995).
0
30
Time, min
60
9. I. V. Kozhevnikov and K. I. Matveev, Usp. Khim. 51
Fig.
3.
Thermoanalytical
curves
for
(11), 1875 (1982).
(NH ) [BiMo O (OH) ] ⋅ 7H O.
4 3
6
18
6
2
10. H. Struve, J. Prakt. Chem. 61, 499 (1854).
11. R. D. Hall, J. Am. Chem. Soc. 29, 692 (1907).
−6Mo3
⎯⎯⎯⎯⎯→
770°C
12. A. V. Oreshkina, G. Z. Kaziev, and T. Yu. Glazunova,
Estestv. Tekh. Nauki, No. 6, 107 (2006).
→
1/2Bi2O3
⋅
6MoO3
1/2Bi O .
2 3
13. B. N. IvanovꢀEmin, S. O. Kin’ones, B. E. Zaitsev, and
G. Z. Kaziev, Zh. Neorg. Khim. 26 (8), 2117 (1981).
14. I. V. Osminkina, G. Kaziev, S. O. Kin’ones, and A. de Ita,
This HPC can be used as a catalyst in the reaction
of soft oxidation of natural gas in a flowꢀthrough
quartz reactor at constant temperature 573 K.
Russ. J. Inorg. Chem. 46 (7), 959 (2001).
15. F. V. Syromyatnikov, Min. Syr’e, No. 6, 908 (1930).
REFERENCES
16. K. Nakamoto, Infrared and Raman Spectra of Inorganic
and Coordination Compounds (Wiley, New York, 1986;
Mir, Moscow, 1991).
1. E. A. Nikitina, Heteropoly Compounds (Goskhimizdat,
Moscow, 1962) [in Russian].
RUSSIAN JOURNAL OF INORGANIC CHEMISTRY Vol. 56 No. 12 2011