Synthesis of Sb2Se3and Bi2Se3Nanoparticles in Ionic Liquids at Low Temperatures and Solid State Structure of [C4C1Im]3[BiCl6]

Article abstract of DOI:10.1002/zaac.201600325

Crystalline Sb₂Se₃nanoparticles were prepared by reaction of SbCl₃with (Et₃Si)₂Se in the presence of oleylamine (OA) in the ionic liquid [C₄C₁Im]Cl, whereas the reaction of (Et

Full text of DOI:10.1002/zaac.201600325

Journal of Inorganic and General Chemistry
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Zeitschrift für anorganische und allgemeine Chemie
DOI: 10.1002/zaac.201600325
Synthesis of Sb Se and Bi Se Nanoparticles in Ionic Liquids at Low
2
3
2
3
Temperatures and Solid State Structure of [C C Im] [BiCl ]
4
1
3
6
[
a]
[a]
[a]
[b]
Manuel Loor, Georg Bendt, Julian Schaumann, Ulrich Hagemann,
Markus Heidelmann,[ Christoph Wölper, and Stephan Schulz*
b]
[a]
[a]
Keywords: Bismuth; Antimony; Selenium; Thermoelectric material; Ionic liquids
Abstract. Crystalline Sb
of SbCl with (Et Si) Se in the presence of oleylamine (OA) in the ence of oleylamine in [C
ionic liquid [C Im]Cl, whereas the reaction of (Et
Im] [BiCl ] (1), which was obtained from the reaction of BiCl
with [C
2
Se
3
nanoparticles were prepared by reaction
tion of the reactive IL [C
4
C
1
Im]
3
[Bi
3
I
12] with (Et
3
Si)
2
Se in the pres-
3
nanoparticles.
3
3
2
4
C
1
Im]I gave phase-pure Bi
2
Se
4
C
1
3
Si)
2
Se with
The chemical composition of the nanoparticles was investigated by
EDX, while possible surface contaminations were studied by XPS and
[C
4
C
1
3
6
3
4
C
1
Im]Cl and structurally characterized by single-crystal X-ray IR spectroscopy. The morphology of the nanoparticles was studied by
diffraction, yielded Bi-rich Bi
2
Se
3
nanoparticles. In contrast, the reac-
SEM and TEM.
(tetradymite type).[9] Both materials have received increasing
interest in recent years as promising TE and TI materials.
Sb Se for instance shows a very high Seebeck coefficient
Introduction
Antimony and bismuth chalcogenides of the general type
2
3
M E , (M = Sb, Bi; E = Se, Te) are promising materials for
–1
2
3
(
1800 μV·K ), but its electrical conductivity (σ
≈
[
1]
several technical applications including batteries, photovol-
–6
–2 –1 –1
[10]
10 –10 Ω ·m ) unfortunately is very low.
However,
[2]
[3]
taics and solar cells, topological insulators (TIs), and ther-
moelectric (TE) materials.[ These applications often require
nanostructured materials such as nanoparticles and thin films.
Nanoparticles can be generally prepared either by top-down
processes such as ball-milling or by bottom-up approaches, i.e.
solvothermal routes, polyol processes, reduction reactions, and
others, which have been established in the past for the size-
electrical conductivity can be significantly enhanced by electri-
4]
[11]
cal doping for instance with Ag Se.
2
Sb Se nanoparticles with definite size and shape were typi-
2
3
[12]
cally synthesized by solvothermal processes, microwave-as-
sisted method,[
13,14]
[11]
and hot injection methods.
Recently,
Sb Se nanowires with diameters ranging from 10 to 20 nm
2
3
and length up to 30 μm were prepared by reaction of tri-
and shape-selective synthesis of binary and ternary antimony
phenylantimony with dibenzyldiselenide.[ Bi Se nanopar-
15]
and bismuth chalcogenides.[5]
2
3
ticles were also obtained from polyol synthesis and micro-
Bismuth selenide Bi Se is a small bandgap semiconductor
2
3
[16]
wave-assisted solvothermal routes, respectively.
[6]
with a direct bandgap, E = 0.35 eV, whereas Sb Se has an
g
2
3
We are generally interested in the synthesis of nanostruc-
tured group 15 chalcogenide materials by gas-phase processes
such as metal organic chemical vapor deposition
indirect energy bandgap of 1.21 eV and a direct transition at
[
7]
1
.22 eV according to very recent calculations. The structure
[8]
of Sb Se , which crystallizes in the space group Pnma, can
2
3
17]
[18]
(
MOCVD)[ and atomic layer deposition (ALD),
which
be described as one-dimensional chains along the direction of
were successfully applied in our group for the deposition of
thin films of binary and ternary group 15 chalcogenides.
Furthermore, we developed solution-based synthetic routes and
synthesized crystalline Sb E (E = S, Se, Te) and Bi Te nano-
the b axis, which are cross-linked to give the 3D orthorhombic
¯
structure. Bi Se crystallizes in the space group R3m
2
3
2
3
2
3
*
Prof. Dr. S. Schulz
Fax: +49-201-183-3830
particles by thermal decomposition of metal organic (single
source) precursors in high boiling organic solvents in the pres-
E-Mail: stephan.schulz@uni-due.de
https://www.uni-due.de/ak_schulz/index_en.php
[
19]
ence of capping agents such as PVP or oleylamine (OA).
[
[
a] Inorganic Chemistry and Center for Nanointegration Duisburg-
Essen (CENIDE)
In addition, ionic liquids (ILs) were successfully applied as
novel solvent for the synthesis of Sb Te nanoplates, which
University of Duisburg-Essen
2
3
Universitätsstr. 5–7, S07 S03 C30
45117 Essen, Germany
showed enhanced thermoelectric properties and high figure of
b] Interdisciplinary Center for Analytics on the Nanoscale (ICAN)
[20]
merit values of up to 1.5.
The use of metal organic precur-
NETZ
sors allowed the material synthesis under kinetically controlled
reaction conditions at low temperatures due to the weak metal-
carbon bonds. Unfortunately, their low thermal stability, which
is in particular true for Bi-containing compounds, often limits
Carl-Benz-Str. 199
47047 Duisburg, Germany
Supporting information for this article is available on the WWW
under http://dx.doi.org/10.1002/zaac.201600325 or from the au-
thor.
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their applicability in material synthesis due to the occurrences
of unwanted side reactions such as thermal decomposition re-
actions. For instance, the synthesis of Bi Te was often ac-
2
3
companied by the formation of elemental Bi or Bi-rich phases
as side-products. We became therefore interested in the devel-
opment of alternative precursors and reaction processes.
We now report on the synthesis of phase-pure Sb Se and
2
3
Bi Se nanoparticles by IL-based wet chemical approaches.
2
3
The composition, phase purity and morphology of the materi-
als were investigated by IR, EDX, XPS, XRD, SEM, and TEM
and the solid-state structure of [C C Im] [BiCl ] (1) is dis-
4
1
3
6
cussed.
Results and Discussion
Figure 1. 29Si NMR spectra of the products of the reaction of
Et Si) Se with [C Im] [Bi 12] (A, B) and BiCl (C, D) at 150 °C.
We recently reported on the synthesis and solid-state struc-
ture of [C C Im] [Bi I ], which was obtained in quantitative
(
3
2
4
C
1
3
3
I
3
4
1
3
3 12
yield by reaction of equimolar amounts of [C C Im]I and BiI ,
4
1
3
The elemental composition of the resulting material as deter-
and its promising potential to serve as Bi source for the synthe-
sis of phase-pure binary (Bi Te ) and ternary ([Bi Sb ] Te )
mined by EDX proved the formation of stoichiometric bismuth
selenide Bi Se (Table 1). According to IR spectroscopy stud-
2
3
x
1–x 2
3
2
3
tetradymite-type metal telluride nanoparticles in an IL-based
wet chemical approach.[21] In order to investigate the synthetic
ies, the material does not contain significant amounts of or-
ganic molecules as was shown by comparing the IR spectrum
of the nanoparticles with those of pure OA, [C C Im]I, and
potential of this soluble and thermally stable Bi-source in more
detail, we expanded our studies on the synthesis of the corre-
sponding bismuth selenide Bi Se (Scheme 1).
4
1
acetonitrile (Figure 2).
2
3
2 3 2 3
Table 1. EDX results of Bi Se and Sb Se .
Bismuth /At% Antimony /At%
Selenium /At%
Bi
Sb
2
Se
Se
3
40.5Ϯ0.6
–
–
59.5Ϯ1.5
57.5Ϯ1.0
2
3
42.5Ϯ1.5
2 3
Scheme 1. Synthesis of Bi Se nanoparticles.
(
Et Si) Se reacts with [C C Im] [Bi I ] in a solution of
3 2 4 1 3 3 12
1
0 mL of [C C Im]I in the presence of OA at 150 °C with
4 1
formation of a black precipitate, which was isolated by centri-
fugation and purified by repeatedly washing with acetonitrile
and hexane (3ϫ). The reaction also proceeded at lower tem-
peratures such as 80 °C, but crystalline Bi Se was only ob-
2
3
tained at higher temperature. The soluble reaction products
2
9
were further investigated by Si NMR spectroscopy to ident-
ify the reaction mechanism (Figure 1).
(
Et Si) Te reacted with [C C Im] [Bi I ] in [C C Im]I with
3 2 4 1 3 3 12 4 1
formation of Et SiI (dehalosilylation reaction) and Si Et (1:3
3
2
6
molar ratio), which was formed by homolytic cleavage of the
Te–Si bond,[ while the reaction proceeded with elimination
of silylamine (Et SiOA) and Si Et (2:1 molar ratio) in the
21]
Figure 2. IR spectra of Bi
of (Et Si) Se with [C Im]
OA at 150 °C.
2
Se
3
nanoparticles synthesized by reaction
12] in [C Im]I in the presence of
3
22]
2
6
presence of OA.[ In contrast, the reaction of (Et Si) Se with
3
2
4
C
1
3
[Bi
3
I
4 1
C
3
2
[
C C Im] [Bi I ] in the absence of OA exclusively yielded
4 1 3 3 12
Si Et , while Et SiOA and Si Et (2:1 molar ratio) were
formed in the presence of OA as was shown by Si NMR carbon as well as a minimal amount of iodine, which most
In contrast, XPS studies (Figure 3) prove the existence of
2
6
3
2
6
2
9
spectroscopy (Figure 1A, B). The formation of Et SiI was not likely result from a residual IL layer on the surface of the
3
detected at all. These findings prove that OA is more reactive nanoparticles. This thin surface layer cannot be detected by IR
toward (Et Si) Se compared to the iodide anion, while in the spectroscopy but by XPS due to the higher surface sensitivity.
3
2
absence of OA, the homolytic Se–Si bond breakage reaction The binding energy of the main lines in the Bi and Se signals
[23]
is preferred.
agree well with literature data of Bi Se surfaces.
Selenium
2
3
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Figure 3. XPS Bi4f and Se 3d signals of Bi
2
Se
3
nanoparticles synthesized by reaction of (Et
3
Si)
2
Se with [C
4
C
1
Im]
3
[Bi
3
I12] in [C
4
C
1
Im]I in the
presence of OA at 150 °C. No change in the metal oxide content is visible upon exposure to air.
oxides (binding energy comparable to SeO ) were hardly vis- good agreement with values reported for Bi Se (PDF 901-
2
2
3
ible (see inlet Figure 3), while roughly 5% of the Bi surface 1965). The XRD pattern shows a strong texture effect, since
atoms are either present as bismuth oxides, most likely mixed the hexagons arrange with the c axis perpendicular to the sam-
bismuth oxoselenides [Bi (O Se ) , 90%], or iodides (BiI3 ple holder as was also observed in REM photographs (Fig-
2
x
1–x 3
or BiOI, 10%). The presence of bismuth oxides or iodides in ure 5). As a consequence, the intensity of the (00l) reflections
these low quantities result in a shoulder to the large metal Bi is strongly enhanced as can be seen in particular for the (006)
signal and are not distinguishable.
reflection, whereas the intensity of the (015) reflection is di-
The amount of bismuth and selenium oxides did not increase minished compared to the standard card. In addition, the XRD
upon exposure to air. A very recent XPS study clearly revealed pattern shows anisotropic peak broadening since the Bi Se3
2
that Bi Te and Bi Te Se easily form the corresponding oxides plates are relatively large (ca. 300 nm) but also very thin. For
2
3
2
2
upon expose to air, while Bi Se was significantly more this reason, the XRD pattern shows strong peak broadening
2
3
stable.[
24]
Comparable findings were previously reported
[25]
with exception of the (110) reflection at 43.8°.
and also observed for Bi Te nanoparticles, which were shown
2
3
to form bismuth oxides and tellurium oxides within a day upon
expose to air.[
21]
The material was also investigated by powder X-ray diffrac-
tion (PXRD), which clearly proved the formation of crystalline
Bi Se nanoparticles (Figure 4).
2
3
Figure 5. SEM image of Bi
of (Et Si) Se with [C Im]
OA at 150 °C.
2
Se
3
nanoparticles synthesized by reaction
12] in [C Im]I in the presence of
3
2
4
C
1
3
[Bi
3
I
4 1
C
The morphology of the Bi Se nanoparticles was investi-
2
3
gated by SEM and TEM. According to the SEM studies, the
material contains largely agglomerated hexagonal Bi Se3
2
nanoplates, whose size ranges from 50 to 500 nm (Figure 5).
The agglomeration, which also indicates an almost capping-
layer free surface, has been previously observed for Sb Te3
2
and Bi Te as well as (Sb Bi ) Te nanoparticles as-synthe-
2
3
x
1–x 2
3
sized in ILs.[
20,21]
The shape and size of the hexagonal Bi Se3
2
nanoplates is similar to those synthesized by other wet chemi-
cal bottom-up methods, which typically use shape and size
controlling agents, and clearly results from the tetradymite-
type layer structure. However, compared to standard capping
agents such as oleylamine or PVP, the IL used herein obvi-
Figure 4. PXRD of Bi
Et Si) Se with [C Im]
at 150 °C and reference for Bi
2
Se
3
nanoparticles synthesized by reaction of
12] in [C Im]I in the presence of OA
Se (PDF 901-1965).
(
3
2
4
C
1
3
[Bi
3
I
2
4 1
C
[
26]
3
The peaks can be indexed on the basis of phase-pure Bi Se3 ously binds weaker to the surface and can therefore be easily
2
(
4
PDF 901-1965). The lattice parameters were refined to a = washed away, resulting in the formation of largely agglomer-
.144(9) Å, c = 28.686(5) Å, and V = 426.8(3) Å , and are in ated nanoparticles.
3
[27]
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TEM bright field images show the formation of hexagonal pound 1 crystallizes in the orthorhombic space group Pna21
plates with sizes between 50 to 200 nm. A high-resolution with two formula units in the asymmetric unit (Figure 7).
high-angle annular dark-field (HAADF) image of the Bi Se3
2
structure projected along the [5 10 1] direction is given in Fig-
ure 6 (right), clearly proving the crystalline nature of the mate-
rial. The measured closest distance between two atomic col-
umns is 0.29 nm, which is in good agreement to the value of
0
.287 nm as reported in the literature.[28]
4 1 3 6
Figure 7. Solid state structure of [C C Im] [BiCl ] (1). Probability el-
lipsoids are displayed at 50% probability levels and second disorder
component hydrogen atoms are omitted for clarity. Selected bond
lengths /Å and angles /°: Bi1_1–Cl6_1 2.6790(12), Bi1_1–Cl4_1
2
.6906(11), Bi1_1–Cl2_1 2.7080(10), Bi1_1–Cl3_1 2.7191(10),
Bi1_1–Cl1_1 2.7239(10), Bi1_1–Cl5_1 2.7404(11), Bi1_2–Cl4_2
.6829(10), Bi1_2–Cl5_2 2.6845(13), Bi1_2–Cl1_2 2.6913(10),
Bi1_2–Cl2_2 2.7155(10), Bi1_2–Cl3_2 2.7398(10), Bi1_2–Cl6_2
2
Figure 6. Conventional bright field TEM (left) and HAADF STEM
right) images of Bi Se nanoparticles projected along [5 10 1] direc-
tion. Model structure of Bi Se as overlay (orange: Bi, yellow: Se).
(
2
3
2
8
8
8
.7643(12); Cl6_1–Bi1_1–Cl4_1 86.72(4), Cl6_1–Bi1_1–Cl2_1
5.87(4), Cl4_1–Bi1_1–Cl2_1 92.97(3), Cl6_1–Bi1_1–Cl3_1
9.97(4), Cl4_1–Bi1_1–Cl3_1 175.97(4), Cl2_1–Bi1_1–Cl3_1
9.08(3), Cl6_1–Bi1_1–Cl1_1 90.23(3), Cl4_1–Bi1_1–Cl1_1
2
3
The use of the reactive IL [C C Im] [BiI ], which is easily
4
1
3
12
obtained from the reaction of BiI with an equimolar amount
3
89.37(3), Cl2_1–Bi1_1–Cl1_1 175.32(4), Cl3_1–Bi1_1–Cl1_1
of [C C Im]I, in material synthesis avoids the formation of 88.35(3), Cl6_1–Bi1_1–Cl5_1 174.53(3), Cl4_1–Bi1_1–Cl5_1
4
1
elemental bismuth or bismuth-rich material phases, i.e. BiTe 90.40(4), Cl2_1–Bi1_1–Cl5_1 89.64(3), Cl3_1–Bi1_1–Cl5_1
9
8
8
8
3.09(4), Cl1_1–Bi1_1–Cl5_1 94.40(4), Cl4_2–Bi1_2–Cl5_2
7.24(4), Cl4_2–Bi1_2–Cl1_2 92.97(3), Cl5_2–Bi1_2–Cl1_2
5.75(4), Cl4_2–Bi1_2–Cl_22 94.62(3), Cl5_2–Bi1_2–Cl2_2
7.91(4), Cl1_2–Bi1_2–Cl2_2 169.87(4), Cl4_2–Bi1_2–Cl3_2
or Bi Te in case of bismuth tellurides, as is often observed in
the synthesis of bismuth chalcogenides. This finding most
likely results from its high reactivity but increased thermal sta-
4
3
bility compared to many (organometallic) bismuth sources. 173.96(4), Cl5_2–Bi1_2–Cl3_2 86.97(4), Cl1_2–Bi1_2–Cl3_2
8
8
9
8.33(3), Cl2_2–Bi1_2–Cl3_2 83.44(3), Cl4_2–Bi1_2–Cl6_2
8.15(4), Cl5_2–Bi1_2–Cl6_2 175.34(4), Cl1_2–Bi1_2–Cl6_2
3.79(4), Cl2_2–Bi1_2–Cl6_2 93.16(4), Cl3_2–Bi1_2–Cl6_2
The reactions of Se(SiEt ) with [C C Im] [BiI ] were found
3
2
4
1
3
12
to proceed at temperatures as low as 80 °C, which is higher
than those with Te(SiEt ) , which already occurred at ambient
3
2
97.65(4).
temperature, but below typical reaction temperatures as applied
in polyol processes (up to 250 °C) and in reduction reactions
The BiCl 3– ions can be described as slightly distorted octa-
6
or thermal decomposition reactions.[
29]
The higher reaction hedra. Perpendicular to the a axis, the anions form layers of
temperature in case of the reaction with Se(SiEt ) agrees with interconnected six-membered rings similar to those observed
3
2
the decreasing E–Si bond energy (E = Se, Te) with increasing in the wurzite structure, however, the lower symmetry prevents
atomic number. However, in order to obtain highly crystalline a wurzite-type connection of the layers.
material phases in a reasonable amount of time, reaction tem-
A closer inspection reveals that the opposing Bi–Cl bond
peratures of 100 °C (Te) and 150 °C (Se) as well as prolonged lengths slightly differ (Bi1_1: mean 2.693 Å and 2.729 Å with
reaction times of at least 2–3 h are necessary. Unfortunately, differences ranging from 1.6 to 6.1 pm; Bi1_2: mean 2.686 Å
the homolytic E–Si bond breakage becomes more likely under and 2.740 Å with differences ranging from 2.4 to 8.0 pm) and
these reaction conditions, which results in the formation of that the differing Bi–Cl bond lengths are grouped in a fac ar-
hexaethyldisilane Si Et . However, its formation can be fully rangement. The cisoid Cl–Bi–Cl bond angles range from
2
6
avoided (E = Te) or suppressed (E = Se) if the reactions are 85.87(4) to 94.40(4)° (Bi1_1) and 83.44(3) to 97.65(4)°
performed in the presence of OA, which initially reacts with (Bi1_2), and the transoid Cl–Bi–Cl bond angles deviate from
E(SiEt3)2 with formation of the silylamine (Et SiOA) and linearity [Bi1_1: 174.53(3)–175.97(4)°; Bi1_2: 169.87(4)–
3
chalcogenide polyanions, which then smoothly react with 175.34(4)°]. The deviation from linearity in the hexachlorobis-
[
C C Im] [Bi I ] with formation of phase-pure Bi E .
muthate ion is comparable to that observed in other hexachlo-
4
1
3
3 12
2 3
To further expand the field of application of halogenidobis- robismuthates.[ A statistical analysis of the CSD (mean dif-
30]
muthates as starting reagents in material synthesis, we investi- ference of 10.5 pm with a std. deviation of 10 pm) shows abso-
gated the reaction of BiCl and [C C Im]Cl. The reaction with lute bond lengths ranging from 2.6790(12) to 2.7643(12) Å
3
4 1
a threefold amount of [C C Im]Cl yielded a liquid compound, [CSD mean 2.71(6) Å], whereas the bond angles show the ex-
4
1
from which a single crystal of [C C Im] [BiCl ] (1) was ob- pected values for a slightly distorted octahedron (mean 90.00°
4
1
3
6
tained by re-crystallization from a solution in ethanol. Com- and 174.17°).[
31]
However, considering the standard uncer-
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tainties of the Bi–Cl bond lengths and the standard deviation not yield stoichiometric Sb Se . In remarkable contrast, the
2
3
of the CSD results, these findings, which match theoretical analogous reaction of (Et Si) Se with SbCl in [C C Im]Cl
3
2
3
4 1
expectations, should not be overrated.
and OA yielded phase-pure Sb Se , which was isolated as
2 3
The hexachlorobismuthate(III) anion, a 14e system in which black precipitate and purified by repeatedly washing with
the electron lone pair formally shows a high (formally stereo- acetonitrile and hexane (3ϫ). 29Si NMR spectroscopy studies
chemically inactive) s-character, often shows high variations again proved the formation of Et SiCl and Si Et as was ob-
3
2
6
(
σ) in the Bi–Cl bond lengths and Cl–Bi–Cl angles. The distor- served for the analogous reaction with BiCl (Scheme 2).
3
3
–
tion of the octahedral coordination of the [BiCl6] anion has
been traditionally explained as accommodating the spatial
requirements of the electron lone pair, which points away from
the shortest Bi–Cl bonds in the octahedron, while more recent
studies addressed the distortion to the softness of this specific
anion.[ In addition, the variations can be significantly en-
hanced in case of the presence of intermolecular (weak)
32]
2 3
Scheme 2. Synthesis of Sb Se nanoparticles.
The elemental composition of the material as determined
by EDX proved the formation of highly stoichiometric Sb Se3
[30c]
hydrogen bonding.
Orgel attributed the structural distortion
2
by mixing of the s and p orbital of the cation,[33a] which was
confirmed by Wheeler and Kumar using extended Hückel cal-
culations, according to which the trigonal distortion in the mo-
(Table 1). PXRD studies clearly proved the formation of crys-
talline Sb Se nanoparticles (Figure 8). The peaks can be inde-
2
3
xed on the basis of phase-pure Sb Se (PDF 901–7374). The
2
3
3
–
lecular anion [BiCl6] results from the mixing of the cationic s
orbital (HOMO) and the cationic p orbital (LUMO).
determined lattice parameters [a
= 1.163(2) nm, b =
[33b]
This
z
0.397(6) nm, c = 1.168(1) nm] are in a very good agreement
with the ICSD database for the pure orthorhombic Sb Se3
3–
description implies that the lone pair electrons in [BiCl6] on
the central atom are hybridized toward the longer bonds and
larger angles. In agreement with this description, the shorter
Bi–Cl bonds Bi1_1-Cl2/4/6 and Bi1_2-Cl1/4/5 in 1 correspond
to the smaller Cl–Bi–Cl angles, whereas the longer Bi–Cl
bonds define the larger Cl–Bi–Cl angle. Alternatively, the
bonding situation in the hexachlorobismuthate(III) anion can
2
phase. The XRD pattern shows strong preferred orientation of
the needle-like Sb Se structures. Compared to the standard
2
3
card, the intensity of the (201), (302) and (402) reflections are
strongly enhanced. The Sb Se nanowires preferentially grow
2
3
along the [010] direction as can be seen from the high intensity
of the (h0l) reflections. This conclusion is supported by TEM
and SAED and often observed for Sb Se nanostructures.
be formally described as asymmetrical 4e3c bond or as BiCl3
2
3
with three additionally coordinated chloride anions.
Unfortunately, the reaction of (Et Si) Se with BiCl in a
3
2
3
solution of [C C Im]Cl in the presence of oleylamine did not
4
1
yield phase-pure Bi Se . The reaction proceeded with elimi-
2
3
nation of Et SiCl (dehalosilylation) and formation of Si Et
6
3
2
(2:1 molar ratio) as shown in Figure 1D. Obviously, the chlor-
ide anion is far more reactive than the iodide anion, resulting
in dehalosilylation (Figure 1C), while the less reactive iodide
results in homolytic bond cleavage and formation of Si Et6
2
(Figure 1A). Even though the XRD shows the formation of
crystalline Bi Se material in both cases, the resulting materi-
2
3
als were Bi-rich according to EDX analysis (Bi 50%, Se
50%).
Since [C C Im] [Bi I ] was successfully applied for the
4
1
3
3 12
[21]
synthesis of Bi Se and Bi Te nanoparticles,
we became
2
3
2
3
interested to expand this procedure to the synthesis of the com-
parable antimony chalcogenides and turned our attention
to the synthesis of antimony-containing reactive ILs. Halogen-
Figure 8. PXRD of Sb
Et Si) Se with SbCl in [C
and reference for Sb Se (PDF 900-7374).
2
Se
3
nanoparticles synthesized by reaction of
(
3
2
3
4 1
C Im]Cl in the presence of OA at 150 °C
[
35]
2
–
2
3
idoantimonates such as the [Sb X ] dianions (X = Br, I)
3
11
are well known and were found for instance in
IR spectroscopy (Figure 9) and XPS studies (Figure 10) re-
[34]
[
Cu(MeCN) ] [Sb X ].
We therefore investigated the reac- vealed the existence of an organic capping layer. The carbon
4
2
3 11
tion of SbI with [C C Im]I, but we were not able to crystallize concentration is more pronounced than that observed for the
3
4 1
a specific halogenidoantimonate. The same was true for the Bi Se particles. The binding energy of the main lines in the
2
3
reaction of SbCl with [C C Im]Cl. We therefore turned our Sb and Se signals agree well with literature data of Sb Se
3
4
1
2
3
attention to the reaction of a mixture of SbI , [C C Im]I, and surfaces.[ However, roughly 40% of the Sb surface atoms
36]
3
4 1
OA with (Et Si) Se, but this reaction only yielded a Sb-rich of an as-prepared sample are present as antimony oxide or
3
2
material phase according to EDX analysis (Sb 59% Se 39%, oxoselenide [Sb O or Sb (Se O ) ] but the oxygen content
2
3
2
x 3–x 2
I 2%) rather than the expected Sb Se . Even prolonged reac- stays constant upon exposure to air. The oxygen signal at
2
3
tion times (24 h) and high reaction temperatures (200 °C) did 532 eV binding energy increases strongly, showing the oxid-
Z. Anorg. Allg. Chem. 0000, 0–0
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© 0000 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim

Journal of Inorganic and General Chemistry
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ARTICLE
Zeitschrift für anorganische und allgemeine Chemie
ation of the capping layer and carbon contaminations on the
surface. The Se 3d signal does show a small oxide peak only
after one day of exposure to air. No further increase of the Se-
oxide content is visible after that. However, the error in the
determination of the Se-oxide [Sb (Se O ) ] intensity is quite
2
x 1–x 3
large, due to the weak signal and hence small signal to noise
ratio.
Figure 11. SEM image of Sb
tion of (Et Si) Se with SbCl
50 °C.
2
Se
in [C
3
nanoparticles synthesized by reac-
Im]Cl in the presence of OA at
3
2
3
4 1
C
1
up to 5 μm and diameters of about 30 nm. The Sb Se3
2
nanowires are grown along the [010] direction of the stibnite
structure in Pnma setting. A high-resolution image of a Sb Se3
2
nanowire projected along the [001] direction is given in Fig-
ure 12 (right). Due to the contrast in HAADF mode being sen-
sitive to the atomic number Z, atomic columns containing only
Se can be distinguished from mixed SbSe columns. The mea-
sured distance of the (010) planes is 0.392 nm, which is in
good agreement to value of d
= 0.396 nm reported in the
10
0
literature.[ A model structure of Sb Se is overlaid for com-
38]
2
3
parison.
Figure 9. IR spectra of Sb nanoparticles synthesized by reaction of
2
Se
3
(
Et Si) Se with SbCl in [C C Im]Cl in the presence of OA at 150 °C.
3
2
3
4 1
The morphology of the nanoparticles was investigated by
SEM and TEM (Figure 11).
SEM photographs proved the formation of agglomerated
Sb Se nanowires with a high aspect ratio. They are up to 5 μm
2
3
in length and show diameters of about 30 nm (Figure 11),
which is comparable to those previously obtained by polyol
processes (30–50 nm)[ or by thermal decomposition of the
37]
[19b]
single source precursors (Et Sb) Se and Et SbSe.
2
2
3
Figure 12. HAADF STEM images of Sb
2 3
Se nanoparticles in [001]
2
Figure 12 shows HAADF STEM images of the Sb Se3
orientation; structure model of Sb Se as an overlay (red: Sb, green:
2
3
nanowires. The nanowires have a big aspect ratio with lengths Se).
Figure 10. XPS Sb 3d and Se 3d signal of Sb
2 3 3 2 3 4 1
Se nanoparticles synthesized by reaction of (Et Si) Se with SbCl in [C C Im]Cl in the presence
of OA. The intensities of the signals do not change strongly upon exposure to air.
Z. Anorg. Allg. Chem. 0000, 0–0
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© 0000 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim

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ARTICLE
Zeitschrift für anorganische und allgemeine Chemie
H), 1.79 (dt, JH,H = 14.8, 2JH,H = 7.5 Hz, 2 H), 1.29 (m, 2 H), 0.93
(
1
Conclusions
3
t, JH,H = 7.3 Hz, 3 H) ppm.
Phase-pure crystalline group 15 selenides M Se (M = Sb,
2
3
Bi) were synthesized under mild reaction conditions by reac- Synthesis of [C
4 1 3 3 4 1
C Im] [Bi I12]: [C C Im]I (14.91 g, 0.561 mol) and
BiI (27.57 g, 0.468 mol) were added to ethanol (500 mL) and the
tion of (Et Si) Se with SbCl in [C C Im]Cl or by reaction
3
3
2
3
4 1
resulting suspension was stirred at ambient temperature for 5 d. The
resulting bright yellow solid was separated via filtration, washed with
with the reactive IL [C C Im] [Bi I ] containing the tri-
4
1
3
3 12
3
–
anionic halogenidobismuthate [Bi I ] . Both reactions were
3
12
1
00 mL of ethanol and carefully dried for 72 h under dynamic vacuum
at ambient temperature. Yield: 30.87 g (77.16%). Melting point:
8 °C. Elemental analysis (EDX): Bi: 19.8Ϯ1 at%, I: 80.2Ϯ1.7 at%.
performed in the presence of oleylamine, which was found to
effectively suppress the homolytic Se–Si bond cleavage reac-
9
tion, and are scalable to produce of up to 10 g of the Sb Se3
1
2
6
H NMR (300 MHz, 25 °C, [D ]DMSO): δ = 9.11 (s, 1 H), 7.73 (dt,
and Bi Se nanoparticles. In contrast, the reaction of
1J
2
= 1.8 Hz, 2 H), 4.16 (t, 3JH,H = 7.2 Hz, 2 H), 3.85
2
3
H,H H,H
= 20.2, J
3
(
Et Si) Se with [C C Im] [BiCl ] (1), whose solid-state struc- (s, 3 H), 1.76 (m, 2 H), 1.29 (m, 2 H), 0.93 (t, J
H,H
= 7.3 Hz, 3 H)
3
2
4
1
3
6
ture was determined by single-crystal X-ray diffraction, in the ppm.
presence of oleylamine did not yield phase-pure Bi Se . The
2
3
Synthesis of [C
4 1 3 6 4 1
C Im] [BiCl ]: [C C Im]Cl (1.25 g, 7.18 mmol) and
crystalline Sb Se and Bi Se nanoparticles are covered by a
2
3
2
3
BiCl (0.75 g, 2.37 mmol) were stirred at 120 °C for 4 h. The resulting
highly viscous, white liquid was used without further purification.
Yield: 2.0 g (100%). Elemental analysis (EDX): Bi: 13.8Ϯ0.5 at%,
3
thin IL layer according to XPS results. The nanoparticles are
relatively stable toward oxidation, in contrast to previously re-
[21]
ported Bi Te nanoparticles.
SEM and TEM studies proved
the formation of largely agglomerated nanoparticles, which in
case of Sb Se nanowires exhibited a high aspect ratio. The
1
2
3
Cl: 86.2Ϯ2 at%. H NMR (300 MHz, 25 °C, [D
6
]DMSO): δ = 9.41
s, 1 H), 7.79 (dt, JHH = 20.3,, JH,H = 1.7 Hz, 2 H), 4.21 (t, 3JH,H
1
2
(
=
3
2
3
7.2 Hz, 2 H), 3.89 (s, 3 H), 1.75 (m, 2 H), 1.23 (m, 2 H), 0.86 (t, J
H,H
use of the reactive Bi-containing IL [C C Im] [Bi I ] has the = 7.3 Hz, 3 H) ppm.
4
1
3
3 12
great advantage that the concentration of Bi, which must be
provided for the formation of Bi Se , is relatively low. As a
consequence, the formation of Bi-rich material phases or ele-
mental bismuth is avoided.
Synthesis of [C
SbCl
4
C
1
Im]
3
[SbCl
6
]: [C
4
C
1
Im]Cl (1.40 g, 8.04 mmol) and
2
3
3
(0.60 g, 2.66 mmol) were stirred at 120 °C for 4 h. The resulting
highly viscous, clear liquid was used without further purification.
Yield: 2 g (100%). Elemental analysis (EDX): Sb: 14.9Ϯ1.2 at%, Cl:
1
85.1Ϯ1.6 at%. H NMR (300 MHz, 25 °C, [D
6
]DMSO): δ = 9.38 (s,
3
1
H), 7.80 (m, 2 H), 4.18 (t, JH,H = 7.2 Hz, 2 H), 3.86 (s, 3 H), 1.75
Experimental Section
3
(
m, 2 H), 1.23 (m, 2 H), 0.87 (t,, JH,H = 7.3 Hz, 3 H).
Synthetic procedures including the synthesis of the IL and thermolysis
experiments were performed under inert gas conditions (argon atmo-
sphere) in a glovebox or using standard Schlenk techniques. Aceto-
nitrile (99.9+% extra dry, Acros), 1-chlorobutane (99%, ABCR), and stirred at 100 °C for 30 min. (Et
N-methylimidazole (99+%, Sigma Aldrich) were commercially avail-
Synthesis of Sb
(400 mg, 1.8 mmol), olelyamine (1 mL), and [C
Si) Se (200 μL, 0.7 mmol) was added
to the resulting solution, and the mixture was thoroughly stirred. The
able and used as received, wheres ethyl acetate (J. T. Baker) was dis- black suspension was stirred at 150 °C for 12 h. The formed colloidal
2
Se
3
Nanoparticles: In a centrifuge tube SbCl
3
4 1
C
Im]Cl (4 g) were
3
2
tilled prior to use. (Et
method.[
3
Si)
2
Se was prepared according to a literature solution was centrifuged (2500 rpm) and washed with 6ϫ15 mL
acetonitrile. The separated particles were dried in vacuo at ambient
temperature.
39]
Synthesis of 1-Butyl-3-methylimidazolium Chloride [C
4 1
C Im]Cl:
In a 100 mL round-bottom flask 1-methylimidazole (8.1 mL, 10 mmol) Synthesis of Bi Se Nanoparticles: In
a
centrifuge tube
2
3
and 1-butylchloride (13.5 mL, 13 mmol) were dissolved in acetonitrile
50 mL). The resulting solution was stirred at 60 °C for 5 d. Afterwards
[C C Im] [Bi I ] (1400 mg, 1.6 mmol), olelyamine (1 mL), and
[C C Im]I (4 g) were stirred at 100 °C for 30 min. (Et Si) Se (200 μL,
4 1 3 2
4
1
3
3 12
(
the solvent was removed in vacuo until a viscous, yellow oil was re-
ceived. The oil was added dropwise to 200 mL ice-cooled and stirred
0.7 mmol) was added to the resulting red solution, and thoroughly
stirred. The black suspension was stirred at 150 °C for 12 h. The
ethyl acetate. The resulting white powder was separated by filtration, formed colloidal solution was centrifuged (2500 rpm) and washed with
washed with further cool ethyl acetate and finally dried in vacuo. 6ϫ15 mL acetonitrile. The separated particles were dried in vacuo at
1
Yield: 16.77 g (96.5%). H NMR (300 MHz, 25 °C, [D
6
]DMSO): δ =
ambient temperature.
3
2
9
J
.20 (s, 1 H), 7.76 (dt, JH,H = 12.64, JH,H = 1.65 Hz, 2 H), 4.17 (t,
3
3
3
1
13
1
H,H = 7.2 Hz, 2 H), 3.86 (s, 3 H), 1.77 (dt, JH,H = 14.9, JH,H
=
NMR Spectroscopy: H (300 MHz) and C{ H} (75.5 MHz) NMR
spectra (δ in ppm) were recorded with a Bruker Avance DPX-300 spec-
trometer and referenced to internal [D ]DMSO ( H: δ = 2.50; C: δ =
6
3
7
.4 Hz, 2 H), 1.24 (dq, JH,H = 14.3, 3
JH,H = 7.2 Hz, 2 H), 0.90 (t,
3
1
13
J
H,H = 7.3 Hz, 3 H) ppm.
1
13
3
39.51 ppm) or CDCl ( H: δ = 7.26; C: δ = 77.16 ppm).
Synthesis of 1-Butyl-3-methylimidazolium Iodide [C
4 1
C Im]I: 1-
Methylimidazole (22 mL, 0.276 mol) was dissolved in acetonitrile
IR Spectroscopy: IR spectra were recorded in a glovebox with an
100 mL), and 1-butyliodide (0.308 mol, 35 mL) was added dropwise ALPHA-T FT-IR spectrometer equipped with a single reflection ATR
(
in the dark at 0 °C. The solution was stirred at ambient temperature
for 12 h and all volatiles were removed under dynamic vacuum. The
resulting residue was washed with 150 mL of ethyl acetate. After re-
moval of the solvent, the remaining yellowish oil was dried for 72
sampling module.
Single Crystal X-ray Diffraction: Crystallographic data of 1 were
collected with a Bruker D8 Kappa APEX2 diffractometer (Mo-K
ation, λ = 0.71073 Å) at 100(2) K: [C24 45BiCl ], M = 839.34, col-
orless crystal, (0.199ϫ0.173ϫ0.116 mm); orthorhombic, space group
Pna2 ; a = 32.5929(14) Å, b = 12.6604(5) Å, c = 16.6457(7) Å; α =
α
radi-
1
h under dynamic vacuum at 50 °C. Yield: 59.47 g (81%). H NMR
H
6 6
N
1
(
1
300 MHz, 25 °C, [D
6
]DMSO): δ = 9.14 (s, 1 H), 7.76 (dt, JH,H
=
2
3.5, JH,H = 1.7 Hz, 2 H), 4.19 (t, 3JH,H = 7.2 Hz, 2 H), 3.88 (s, 3
1
Z. Anorg. Allg. Chem. 0000, 0–0
7
© 0000 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim

Journal of Inorganic and General Chemistry
www.zaac.wiley-vch.de
ARTICLE
Zeitschrift für anorganische und allgemeine Chemie
3
–1
9
=
0°, β = 90°, γ = 90°, V = 6868.7(5) Å ; Z = 8; μ = 5.624 mm ; ρcalc
Acknowledgements
–3
1.623 g·cm ; 196857 reflections (θmax = 33.252°), 24997 unique
int = 0.0384); 695 parameters; Flack-Parameter x = 0.458(3); largest
max./min in the final difference Fourier synthesis 1.300 e·Å /
0.986 e·Å ; max./min. transmission 0.48/0.27; R
σ(I)], wR = 0.0526 (all data). The solid-state structure of 1 is shown
in Figure 7. The structure was solved by Direct Methods (SHELXS-
and refined anisotropically by full-matrix least-squares on F
SHELXL-2014).[41] Absorption corrections were performed numeri-
cal based on indexed faces (Bruker AXS APEX2). Hydrogen atoms
were refined using a riding model or rigid methyl groups. The crystal
was twinned by inversion and the model refined accordingly. One of
the butyl groups is disordered over two positions. The minor com-
pound could only be refined with a single mutual isotropic displace-
ment parameter. The ADP of the major component suggests further
disorder that could not be resolved.
(R
S. Schulz acknowledges financial support by the Deutsche Forschungs-
gemeinschaft (DFG) within the Priority Program SPP 1708 “Material
Synthesis near Room Temperature“ and the University of Duisburg-
Essen.
–
3
–3
–
2
1
= 0.0283 [I Ͼ
2
[40]
2
9
(
7)
References
[
1] a) D. Y. W. Yu, H. E. Hoster, Sci. Rep. 2014, 51, 4562/1–4562/6;
b) D. Y. W. Yu, P. V. Prikhodchenko, Nat. Commun. 2013, 4,
2922–2928; c) P. V. Prikhodchenko, J. Gun, Chem. Mater. 2012,
24, 4750–4757.
[
2] a) Y. C. Choi, T. N. Mandal, W. S. Yang, Y. H. Lee, S. H. Im,
J. H. Noh, S. I. Seok, Angew. Chem. 2014, 126, 1353–1357; An-
gew. Chem. Int. Ed. 2014, 53, 1329–1333; b) F. T. F. O’Mahony,
U. B. Cappel, N. Tokmoldin, T. Lutz, R. Lindblad, H. Rensmo,
S. A. Haque, Angew. Chem. 2013, 125, 12269 –12273; Angew.
Chem. Int. Ed. 2013, 52, 12047–12051; c) J. A. Chang, J. H.
Rhee, S. H. Im, Y. H. Lee, H.-J. Kim, S. I. Seok, M. K. Nazeerud-
din, M. Grätzel, Nano Lett. 2010, 10, 2609–2612; d) B. Zhou, J.
Zhu, Nanotechnology 2009, 20, 085604.
Crystallographic data (excluding structure factors) for the structure in
this paper have been deposited with the Cambridge Crystallographic
Data Centre, CCDC, 12 Union Road, Cambridge CB21EZ, UK.
Copies of the data can be obtained free of charge on quoting
the depository number CCDC-1502363 for [C
Fax: +44-1223-336-033; E-Mail: deposit@ccdc.cam.ac.uk, http://
www.ccdc.cam.ac.uk).
4 1 6 6 2
C Im] [BiCl ] (1)
(
[
3] a) W. Liu, Z. Zhang, X. Peng, J. Zhong, Phys. B Cond. Matter
2015, 456, 355–358; b) D. Koumoulis, B. Leung, T. C. Chasapis,
R. Taylor, D. King Jr., M. G. Kanatzidis, L.-S. Bouchard, Adv.
Funct. Mater. 2014, 24, 1519–1528; c) J.-J. Zhou, W. Feng, Y.
Zhang, S. A. Yang, Y. Yao, Sci. Rep. 2014, 514, 3841/1–3841/6;
d) Z. Xu, X. Guo, M. Yao, H. He, L. Miao, L. Jiao, H. Lin, J.
Wang, D. Qian, J. Jia, W. Ho, M. Xie, Adv. Mater. 2013, 25,
Powder X-ray Analysis: PXRD patterns were obtained with a Bruker
D8 Advance powder diffractometer with Cu-K radiation (λ =
.5418 Å, 40 kV and 40 mA) using a silicon single crystal as sample
holder to minimize scattering. The powders were re-dispersed in eth-
anol on the silicon surface and investigated in the range from 10 to
α
1
1557–1562; e) Z. Wang, R. L. J. Qiu, C. H. Lee, Z. Zhang,
X. P. A. Gao, ACS Nano 2013, 7, 2126–2131; f) J. Zhang, C.-Z.
Chang, Z. Zhang, J. Wen, X. Feng, K. Li, M. Liu, K. He, L.
Wang, X. Chen, Q.-K. Xue, X. Ma, Y. Wang, Nat. Commun. 2011,
9
0° 2θ with a step size of 0.01° 2θ with a counting time of 0.6 s.
Rietveld refinement was performed with the program package TOPAS
.0 (Bruker) to determine the lattice parameters and average crystallite
size by use of the Scherrer equation with the program package TOPAS
5
2, 1588/1–1588/6; g) M. Z. Hasan, C. L. Kane, Rev. Mod. Phys.
2010, 82, 3045–3067; h) M. König, S. Wiedmann, C. Brüne, A.
42]
5
.0 (Bruker).[ The background was modelled using Chebyshev poly-
nomials. The structure models of Sb Se (#85676) and Bi Se
#72545) from the ICSD database were used. For each Rietveld refine-
Roth, H. Buhmann, L. W. Molenkamp, X.-L. Qi, S.-C. Zhang,
Science 2007, 318, 766–770; i) F. E. Camino, W. Zhou, V. J.
Goldman, Phys. Rev. Lett. 2005, 95, 246802/1–4.
2
3
2
3
(
[
4] a) H. S. Shin, B. Hamdou, H. Reith, H. Osterhage, J. Gooth, C.
Damm, B. Rellinghaus, E. Pippel, K. Nielsch, Nanoscale 2016,
ment, the instrumental correction as determined with a standard pow-
der sample from NIST (National Institute of Standards and Technol-
ogy) as standard reference material [SRM 660b; a(LaB6) = 4.15689 Å]
was taken into account.
8, 13552–13557; b) G. L. Sun, L. L. Li, X. Y. Qin, D. Li, T. H.
Zou, H. X. Xin, B. J. Ren, J. Zhang, Y. Y. Li, X. J. Li, Appl. Phys.
Lett. 2015, 106, 053102; c) Z. Lu, L. P. Tan, X. Zhao, M. Layani,
T. Sun, S. Fan, Q. Yan, S. Magdassi, H. H. Hng, J. Mater. Chem.
C 2013, 1, 6271–6277; d) A. J. Minnich, M. S. Dresselhaus, Z. F.
Ren, G. Chen, Energy Environ. Sci. 2009, 2, 466–479.
XPS: XPS studies were performed with a Versaprobe IITM (Ulvac-
Phi) with monochromatic Al-K light at 1486.6 eV photon energy. The
α
emission angle between analyzer and sample is 45°. The Cu 2p signal
at 932.67 eV binding energy of a sputter-cleaned Cu foil was used as
the binding energy reference. The foil and the powder were put onto
insulating double-sided tape and charging effects were compensated
using a dual-beam neutralizing approach using electrons and slow
moving argon ions.
[5] a) Y. Zhang, G. D. Stucky, Chem. Mater. 2014, 26, 837–848; b)
R. Benoit, V. Hornebecq, F. Weill, L. Lecren, X. Bourrat, M.
Tregner-Delapierre, Mater. Chem. A 2013, 1, 14221–14226; c)
M.-R. Gao, Y.-F. Xu, J. Jiang, S.-H. Yu, Chem. Soc. Rev. 2013,
42, 2986–3017; d) R. J. Mehta, C. Karthik, B. Singh, R. Teki, T.
Borca-Tasciuc, G. Ramanath, ACS Nano 2010, 4, 5055–5060; e)
G. Zhang, Q. Yu, X. Li, Dalton Trans. 2010, 39, 993–1004.
6] B. Pejova, I. Grodzanov, A. Tanu sˇ evski, Mater. Chem. Phys.
[
Electron Microscopy: Particle size and morphology as well as ele-
mental composition of the powders were analyzed by scanning elec-
tron microscopy (SEM) with a Jeol JSM 6510 microscope equipped
with a Bruker Quantax 400 spectrometer (EDX, chemical composi-
tion). High-resolution STEM studies were carried out with a Jeol JEM
2
004, 83, 245–249.
[7] R. Vadapoo, S. Krishnan, H. Yilmaz, C. Marin, Phys. Status Solidi
B 2011, 248, 700–705.
[8] a) N. W. Tideswell, F. H. Kruse, J. D. McCullough, Acta Crys-
tallogr. 1957, 10, 99–102; b) G. P. Voutsas, A. G. Papazoglou,
P. J. Rentzeperis, D. Siapkas, Z. Kristallogr. 2010, 171, 261–268;
c) V. L. Deringer, R. P. Stoffel, M. Wuttig, R. Dronskowski,
Chem. Sci. 2015, 6, 5255–5262.
2
2
200fs microscope equipped with probe-side Cs-corrector operated at
00 kV acceleration voltage.
[
9] R. W. G. Wyckoff, Crystal Structures, 2nd ed., Krieger, Malabar,
986.
Supporting Information (see footnote on the first page of this
article): Spectroscopic data (NMR, IR) of [C Im] [BiCl ] (1),
Im] [SbCl ], BiCl , SbCl , [C Im][Cl] and [C Im][I] as
Se and Sb Se nanoparticles.
1
4
C
1
3
6
[
10] a) X. W. Zheng, Y. Xie, L. Y. Zhu, X. C. Jiang, Y. B. Jia, W. H.
Song, Y. P. Sun, Inorg. Chem. 2002, 41, 455–461; b) L. G. Grib-
nyak, T. B. Ivanova, Inorg. Mater. 1987, 23, 478–482; c) B. R.
[
C
4
C
1
3
6
3
3
4
C
1
4 1
C
well as Rietveld refinements of Bi
2
3
2
3
Z. Anorg. Allg. Chem. 0000, 0–0
8
© 0000 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim

Journal of Inorganic and General Chemistry
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ARTICLE
Zeitschrift für anorganische und allgemeine Chemie
Chakraborty, B. Ray, R. Bhattacharya, A. K. Dutta, J. Phys.
1002; b) L. V. Yashina, J. Sánchez-Barriga, M. R. Scholz, A. A.
Chem. Solids 1980, 41, 913–917.
11] D. Choi, Y. Jang, J. Lee, G. H. Jeong, D. Whang, S. W. Hwang,
K.-S. Cho, S.-W. Kim, Sci. Rep. 2014, 51, 6714/1–7.
12] a) Y. Liang, Y. Wang, J. Wang, S. I. Wu, D. Jiang, J. Lian, RSC
Adv. 2016, 6, 11501–11506; b) R. Jin, G. Chen, C. Yan, D. Chen,
H. Xu, J. Pei, CrystEngComm 2012, 14, 8547–8553; c) L. Guo,
G. B. Ji, X. F. Chang, M. B. Zheng, Y. Shi, Y. D. Zheng, Nano-
technology 2010, 21, 035606; d) Y. Chen, B. Deng, G. B. Cai,
Volykhov, A. P. Sirotina, V. S. Neudachina, M. E. Tamm, A. Vary-
khalov, ACS Nano 2013, 7, 5181–5191; c) H. Bando, K. Koizumi,
Y. Oikawa, K. Daikohara, V. A. Kulbachinskii, H. Ozaki, J. Phys.
Condens. Matter 2000, 12, 5607–5616.
[
[
[26] S. Nakajima, J. Phys. Chem. Solids 1963, 24, 479–485.
[27] a) K. Kadel, L. Kumari, W. Li, J. Y. Huang, P. P. Provencio, Nano-
scale Res. Lett. 2016, 6, 57; b) R. Harpness, A. Gedanken, New
J. Chem. 2003, 27, 1191–1193.
T. K. Zhang, W. F. Dong, W. X. Zhang, A. W. Xu, J. Phys. Chem. [28] S. A. Semiletov, Z. G. Pinsker, Dokl. Akad. Nauk SSSR 1955, 100,
C 2008, 112, 672–679. 1079–1082.
13] Y.-Q. Liu, M. Zhang, F.-X. Wang, G.-B. Pan, J. Mater. Chem. C [29] a) K. Kadel, L. Kumari, W. Li, J. Y. Huang, P. P. Provencio, Nano-
[
[
[
[
2
014, 2, 240–244.
scale Res. Lett. 2011, 6, 57/1–7; b) G. Zhang, W. Wang, X. Lu,
X. Li, Cryst. Growth Des. 2009, 9, 143–150; c) R. Y. Wang, J. P.
Feser, X. Gu, K. M. Yu, R. A. Segalman, A. Majumdar, D. J. Mi-
liron, J. J. Urban, Chem. Mater. 2010, 22, 1943–1945; d) H. Cui,
H. Liu, X. Li, J. Wang, F. Han, X. Zhang, R. I. Boughton, J. Solid
State Chem. 2004, 177, 4001–4006.
14] R. J. Mehta, C. Karthik, W. Jiang, B. Singh, Y. Shi, R. W. Siegel,
T. Borca-Tasciuc, G. Ramanath, Nano Lett. 2010, 10, 4417–4422.
15] G. Chen, W. Wang, C. Wang, T. Ding, Q. Yang, Adv. Sci. 2015,
2
, 1500109.
16] a) J. Buha, R. Gaspari, A. E. Del Rio Castillo, F. Bonaccorso, L.
Manna, Nano Lett. 2016, 16, 4217–4223; b) M. Hong, Z.-G.
Chen, L. Yang, G. Han, J. Zou, Adv. Electron Mater. 2015, 1,
[30] a) F. Wei, Z. Deng, S. Sun, F. Xie, G. Kieslich, D. M. Evans,
M. A. Carpenter, P. D. Bristowe, A. K. Cheetham, Mater. Hori-
zon. 2016, 3, 328–332; b) N. Elfaleh, H. Chouaib, S. Kamoun,
Acta Crystallogr., Sect. E 2013, 69, m666; c) A. S. Rao, U. Ba-
ruah, S. K. Das, Inorg. Chim. Acta 2011, 372, 206–212; d) B.
Zarychta, M. Bujak, J. Zaleski, Z. Naturforsch. B 2004, 59, 1029–
1034.
1
500025/1–9; c) A. Zhuang, J.-J. Li, Y.-C. Wang, X. Wen, Y. Lin,
B. Xiang, X. Wang, J. Zeng, Angew. Chem. 2014, 126, 6543–
547; Angew. Chem. Int. Ed. 2014, 53, 6425–6429; d) Z. Lin, Y.
6
Chen, A. Yin, Q. He, X. Huang, Y. Xu, Y. Liu, X. Zhong, Y.
Huang, X. Duan, Nano Lett. 2014, 14, 6547–6553; e) H. Xu, G.
Chen, R. Jin, D. Chen, Y. Wang, J. Pei, Y. Zhang, C. Yan, Z. Qiu,
CrystEngComm 2014, 16, 3965–3970; f) Y. Min, G. D. Moon,
B. S. Kim, B. Lim, J.-S. Kim, C. Y. Kang, U. Jeong, J. Am. Chem.
Soc. 2012, 134, 2872–2875.
[
31] Cambridge Structural Database, Version 5.37, see also: F. H.
Allen, Acta Crystallogr., Sect. B 2002, 58, 380–388. Analysis
based on 44 hits including a BiCl with co-ordination number of
6
Cl set to 1. The opposing bond lengths were isolated by constrain-
ing the angle at Bi to be Ͻ150°.
[
[
17] a) G. Bendt, J. Sonntag, A. Lorke, W. Assenmacher, U. Hage-
mann, S. Schulz, Semicond. Sci. Technol. 2015, 30, 085021/1–7;
b) G. Bendt, S. Schulz, S. Zastrow, K. Nielsch, Chem. Vap. Depo-
sition 2013, 19, 235–241.
18] a) C. Bae, T. Böhnert, J. Gooth, L. Seulky, S. Lee, H. Kim, S.
Heimann, S. Schulz, H. Shin, K. Nielsch, Semicond. Sci. Technol.
[
[
[
32] A. Guy Orpen, M. J. Quayle, J. Chem. Soc., Dalton Trans. 2001,
1601–1610.
33] a) L. E. Orgel, J. Chem. Soc. 1959, 3815–3819; b) R. A. Wheeler,
P. N. V. P. Kumar, J. Am. Chem. Soc. 1992, 114, 4776.
34] a) S. Pohl, R. Lotz, W. Saak, D. Haase, Angew. Chem. 1989, 101,
3
55–357; Angew. Chem. Int. Ed. Engl. 1989, 28, 344–345; b) C.
Vitzthumecker, A. Pfitzner, Z. Anorg. Allg. Chem. 2014, 640,
366.
2
014, 29, 064003/1–7; b) S. Zastrow, J. Gooth, T. Böhnert, S.
Heiderich, W. Töllner, S. Heimann, S. Schulz, K. Nielsch,
Semicond. Sci. Technol. 2013, 28, 035010/1–6.
2
[
[
35] R. Caracas, X. Gonze, Phys. Chem. Minerals 2005, 32, 295–300.
36] a) G. Chen, J. Zhou, J. Zuo, Q. Yang, Appl. Mater. Interfaces
[
19] a) M. Rusek, G. Bendt, C. Wölper, S. Schulz, Eur. J. Inorg. Chem.
2
016, 3673–3679; b) S. Heimann, W. Assenmacher, O. Prymak,
2
016, 8, 2819–2825; b) C. D. Wagner, A. V. Naumkin, A. Kraut-
S. Schulz, Eur. J. Inorg. Chem. 2015, 14, 2407–2415; c) G. Bendt,
A. Weber, S. Heimann, W. Assenmacher, O. Prymak, S. Schulz,
Dalton Trans. 2015, 44, 14272–14280; d) S. Schulz, S. Heimann,
J. Friedrich, M. Engenhorst, G. Schierning, W. Assenmacher,
Chem. Mater. 2012, 24, 2228–2234.
Vass, J. W. Allison, C. J. Powell, J. R. Rumble Jr., NIST
Standard Reference Database 20, Version 3.4. (web version)
(
http:/srdata.nist.gov/xps/).
37] a) Z. Deng, M. Mansuripur, A. J. Muscat, Nano Lett. 2009, 9,
015–2020; b) W. Tao, J. Wang, D. Wu, J. Chang, F. Wang, Z.
[
[
2
[
20] S. Heimann, S. Schulz, J. Schaumann, A. Mudring, J. Stölzel, F.
Maculewicz, G. Schierning, J. Mater. Chem. C 2015, 3, 10375–
Gao, F. Xu, K. Jiang, Dalton Trans. 2013, 42, 11411–11417; c)
H. Zhang, M. Ge, L. Yang, Z. Zhou, W. Chen, Q. Li, L. Liu, J.
Phys. Chem. C 2013, 117, 10285–10290.
1
0380.
[
[
21] M. Loor, G. Bendt, C. Wölper, W. Assenmacher, S. Schulz, Dal-
ton Trans. 2016, 45, 15326–15335.
22] S. Schulz, S. Heimann, K. Kaiser, O. Prymak, W. Assenmacher,
J. T. Brüggemann, B. Mallik, A.-V. Mudring, Inorg. Chem. 2013,
38] ICSD651518: O. M. Aliev, E. V. Magerramov, P. G. Rustamov,
Russ. J. Inorg. Chem. (Z. Neorgan. Khimii) 1977, 22, 1539–1541.
39] M. R. Detty, M. D. Seidler, J. Org. Chem. 1982, 47, 1354–1356.
40] G. M. Sheldrick, Acta Crystallogr., Sect. A 1990, 46, 467–473.
41] a) G. M. Sheldrick, SHELXL-2014, Program for the Refinement
of Crystal Structures University of Göttingen, Göttingen, Ger-
many 2014; see also: G. M. Sheldrick, Acta Crystallogr., Sect. A
2008, 64, 112–122. shelXle, A Qt GUI for SHELXL: b) C. B.
Hübschle, G. M. Sheldrick, B. Dittrich, J. Appl. Crystallogr. 2011,
44, 1281–1284.
[
[
[
5
2, 14326–14333.
[
23] a) A. J. Green, S. Dey, Y. Q. An, B. O’Brien, S. J. O’Mullane, B.
Thiel, A. C. Diebold, arXiv:1601.04057v1 [cond-mat.mtrl-sci]; b)
C. D. Wagner, A. V. Naumkin, A. Kraut-Vass, J. W. Allison, C. J.
Powell, J. R. Rumble Jr., NIST Standard Reference Database 20,
Version 3.4. (web version) (http:/srdata.nist.gov/xps/).
[24] C. R. Thomas, M. K. Vallon, M. G. Frith, H. Sezen, S. K. Kush-
waha, R. J. Cava, J. Schwartz, S. L. Bernasek, Chem. Mater.
[42] P. Scherrer, Nachr. Ges. Wiss. Gött. Math.-Phys. Kl. 1918, 2, 98–
100.
2
016, 28, 35–39.
[
25] a) C. R. Thomas, G. Sahasrabudhe, S. K. Kushwaha, J. Xiong,
Received: September 9, 2016
R. J. Cava, J. Schwartz, Phys. Status Solidi RRL 2014, 8, 997–
Published Online: ᭿
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© 0000 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim

Journal of Inorganic and General Chemistry
www.zaac.wiley-vch.de
ARTICLE
Zeitschrift für anorganische und allgemeine Chemie
M. Loor, G. Bendt, J. Schaumann, U. Hagemann,
M. Heidelmann, C. Wölper, S. Schulz* .......................... 1–10
Synthesis of Sb Se and Bi Se Nanoparticles in Ionic Liquids at
2
3
2
3
Low Temperatures and Solid State Structure of [C C Im] [BiCl ]
4
1
3
6
Z. Anorg. Allg. Chem. 0000, 0–0
10
© 0000 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim