Twinned TATB nanobelts: Synthesis, characterization, and formation mechanism

Article abstract of DOI:10.1039/c1ce05599b

Twinned TATB nanobelts were directly synthesized using a water/AOT/toluene microemulsion system. Here, urea has been used as an aminating agent, which has been proven to play an important role in the formation of such a nanostructure. X-ray diffraction (XRD), Fourier transform infrared (FT-IR) spectroscopy, and high performance liquid chromatography (HPLC) were used to characterize the composition of the as-synthesized samples. Electron microscopic studies indicated that the morphology and size of the TATB nanobelts can be readily tuned by varying experimental parameters. Transmission electron microscopy (TEM) and selected area electron diffraction (SAED) studies showed that the TATB nanobelts possess mirror symmetry, each of which grow along the [001] direction. A possible mechanism was also proposed to account for the growth of these twinned TATB nanobelts prepared by the microemulsion system. The Royal Society of Chemistry 2011.

Full text of DOI:10.1039/c1ce05599b

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PAPER
Twinned TATB nanobelts: synthesis, characterization, and formation
mechanism
Bing Huang, Minhua Cao,*ab Xinglong Wu, Fude Nie, Hui Huang* and Changwen Hu*
ab
d
c
c
ab
Received 20th May 2011, Accepted 26th July 2011
DOI: 10.1039/c1ce05599b
Twinned TATB nanobelts were directly synthesized using a water/AOT/toluene microemulsion system.
Here, urea has been used as an aminating agent, which has been proven to play an important role in the
formation of such a nanostructure. X-ray diffraction (XRD), Fourier transform infrared (FT-IR)
spectroscopy, and high performance liquid chromatography (HPLC) were used to characterize the
composition of the as-synthesized samples. Electron microscopic studies indicated that the morphology
and size of the TATB nanobelts can be readily tuned by varying experimental parameters.
Transmission electron microscopy (TEM) and selected area electron diffraction (SAED) studies
showed that the TATB nanobelts possess mirror symmetry, each of which grow along the [001]
direction. A possible mechanism was also proposed to account for the growth of these twinned TATB
nanobelts prepared by the microemulsion system.
1
. Introduction
strategies, for instance, chemical/physical vapor deposition
8,9
10
CVD) methods, solution techniques, and so on. Unfortu-
(
One-dimensional (1D) nanostructures, including nanorods,
nanowires, nanotubes, and nanobelts, have received extraordi-
nary attention in the past decades because of their interesting
geometries, unique properties in optics, electrics, and optoelec-
tronics, and potential applications in nanoscale electronic and
nately, the formation of twinned bi-crystals is mainly related to
some critical growth conditions, which makes the preparation of
twinned nanostructures more difficult. In the view of this fact,
there are only a few approaches, especially facile and simple
methods, to acquire twinned nanostructures. Moreover, to the
best of our knowledge, reports of twinned bi-crystals have mainly
1–3
optoelectronic devices. Subsequently, many kinds of inter-
4
esting nanostructures, such as hierarchical structures, hetero-
11
12
13
focused on metals, metal nitrides, metal chalcogenides, and
so forth, most of which have twin planes at a constant spacing
and thus exhibit a zigzagged 1D nanostructure, and twinned
nanostructures of organic small-molecules have not yet been
reported due to their van der Waals or other weak intermolecular
interactions among molecules. Therefore, studies on the
synthesis and performance evaluation of twinned organic
nanomaterials are of great importance.
5
6
structures, two-dimensional superlattices, and so on, spring up
due to their special structures associated with their interesting
physical and chemical properties one after the other. Recently, as
another interesting morphology, bi-crystalline (twinned) nano-
structures have received increasing attention. It has been
demonstrated that the twin boundary in the twinned nano-
structures, the special region, could change the band-structure
engineering of a semiconductor, which has a significant impact
1
6 6 6 6
,3,5-Triamino-2,4,6-trinitrobenzene (TATB, C H N O ) has
7
on the electronic properties of materials. The design and
been extensively used in modern nuclear warheads and nonlinear
14
synthesis of nanostructures with such a special configuration
therefore play a critical role in tuning the properties of the
materials. To date, various twinned nanorods, nanowires, and
nanobelts of inorganic materials have been prepared by some
optical (NLO) fields due to its high energy-density and strong
15,16
second harmonic generation (SHG) efficiency.
It has been
shown that TATB exhibits significant intra- and inter-molecular
hydrogen bonds in a graphite-like crystal structure (Fig. 1),
which may be the major contributor to the extraordinary
a
17,18
Key Laboratory of Cluster Science, Ministry of Education of China,
Department of Chemistry, Beijing Institute of Technology, Beijing,
stability of TATB under thermal and mechanical shock.
Because of these strong interactions which are different from
covalent bonds, TATB is barely soluble in the most common
solvents, and thus most of the methods commonly used in the
synthesis of organic small-molecule nanomaterials, such as
solvent/non-solvent recrystallization, solvent volatilization,
anodic alumina template, and the surfactant-assisted method, do
not work for the fabrication of TATB nanostructures. Therefore,
the synthesis of TATB nanostructures with at least one
1
+
b
00081, P. R. China. E-mail: caomh@bit.edu.cn; cwhu@bit.edu.cn.; Fax:
86-10-68912631; Tel: +86-10-68912631
State Key Laboratory of Explosion Science and Technology, Beijing
Institute of Technology, Beijing, 100081, P. R. China
c
Institute of Chemical Materials, China Academy of Engineering Physics,
Mianyang, 621900, P. R. China. E-mail: huanghui@caep.ac.cn; Fax:
+
d
86-816-2495856; Tel: +86-816-2495301
Beijing National Laboratory for Molecular Sciences, Institute of
Chemistry, Chinese Academy of Sciences, Beijing, 100190, P. R. China
6
658 | CrystEngComm, 2011, 13, 6658–6664
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2. Experimental
2
.1 Chemicals
1
,3,5-Trichloro-2,4,6-trinitrobenzene (TCTNB, 89%) was
recrystallized three times with 1,2-dichloroethane according to the
25
literature and the purity was higher than 99%. Dioctyl sulfo-
succinate sodium salt (AOT, 96%) was purchased from Alfa
Aesar. All of the other reagents used were of analytical purity and
used as received without further purification. Toluene, ammonia,
absolute ethanol, and acetone were purchased from the Chengdu
Union Chemical Industry Reagent Research Institute of China.
1
,2-Dichloroethane, urea, and ammonium carbonate were
purchased from Tianjin Kermel Chemical Reagent Co., Ltd of
China. Ultrapure water (resistivity ¼ 18.2 MU cm) was produced
using a Milli-Q apparatus (Millipore) and filtered using an inor-
ganic membrane with a pore size of 0.02 mm (Whatman Interna-
tional, Ltd.) just before use.
2
.2 Synthesis
The synthesis procedure is as follows: AOT (14.4 g) was dissolved
in 320 mL of toluene to form a colorless transparent solution.
ꢀ1
Fig. 1 (a) Layered structure and (b) planar structure of TATB.
Then, 3 mL of 6 mol L urea aqueous solution was added
dropwise to the above solution under vigorous stirring. After
vigorous stirring of the solution, 1.266 g (4 mmol) TCTNB was
added to the solution and stirred for 15 min, and afterwards, the
newly formed colorless solution was transferred into a 500 mL
dimension as small as possible is a big challenge. Up to now,
most of the attention on TATB has focused on the preparation of
19
ꢁ
TATB microparticles, the theoretical calculation of molecular
round-bottom flask and heated to 90 C, and held at the condi-
20
21
stability and dynamics, radiation-induced degradation, and
tions for 18 h under refluxing conditions with a stirring speed of
22
spectrum study under high-pressure, etc., and no report on the
controllable synthesis of TATB nanostructures with specific
morphologies has been published. Accordingly, developing
a facile and novel method for constructing these structures of
TATB is necessary, especially at the request of current Micro-
Electro-Mechanical Systems (MEMS) of micro/nanoscale ener-
8
00 rpm. Finally, the bottle was allowed to cool to room
temperature. The resulting precipitate was collected and washed
several times with acetone, ultra-pure water, and absolute
ethanol. TATB nanostructures were obtained by the natural
ꢁ
sinking method and drying in air at 80 C for 6 h.
23
getic materials with specific morphologies.
2
.3 Characterization
Herein, we report for the first time a wet chemical route for
synthesizing twinned TATB nanobelts by using urea as an
aminating agent in a microemulsion system. It is well known
Powder X-ray diffraction (XRD) patterns were obtained with
a D8 Advance X-ray diffractometer with Cu-Ka radiation
ꢀ
ꢀ
that urea is generally used as a precipitant agent to offer OH
(l ¼ 1.5418 A). Fourier transform infrared (FT-IR) spectra were
by hydrolysis in the synthesis of inorganic micro/nano-
collected with a Spectrum One IR spectrophotometer from 400
ꢀ1
24
materials, while in our case, we used the other hydrolysis
product of urea, NH3 as an aminating reagent, to directly
synthesize TATB. Compared with those reactions for the
synthesis of TATB by using traditional aminating agents such
to 4000 cm . Field-emission scanning electron microscopy (FE-
SEM) images were obtained with a Hitachi S-4800 field emission
microscope operated at an acceleration voltage of 10 kV.
Transmission electron microscopy (TEM) and selected-area
electron diffraction (SAED) images were captured on a FEI
Tecnai-20 transmission electron microscope at a temperature of
3
as NH gas, ammonia, and ammonium carbonate, our reaction
is controllable by adjusting the hydrolysis rate of urea, and as
a consequence the crystal nucleation and growth of TATB
could be tuned. By using this route, besides twinned nanobelts,
various other TATB micro/nanostructures, such as leaves,
banana leaves, and wedge-shaped ribbons with different sizes,
could be directly synthesized by adjusting experimental
parameters such as reaction time, the molar ratio of water to
surfactant (w) and the concentration of urea. A new formation
mechanism of twinned TATB nanobelts was proposed. To our
knowledge, there is no such report previously on the synthesis
of organic small-molecule micro/nanostructures with different
morphologies using a simple and facile method via a micro-
emulsion-assisted wet chemical route.
ꢁ
ꢀ174 C operating at 200 kV accelerating voltage by drop casting
the nanobelt dispersions on copper grids coats with Formvar and
carbon film (SPI, West Chester. PA). Differential scanning
calorimetric analyses (DSC) were carried out on a Q600 unit in
ꢁ
ꢀ1
a N atmosphere with a heating rate of 10 C min . Analytical
2
high performance liquid chromatography (HPLC) was per-
formed on a Agilent 1100 high performance liquid chromatog-
raphy instrument coupled to a UV-detector using a Nucleosil
ꢀ
(ID ꢂ L ¼ 4.6 ꢂ 250 mm, analytical column 600 A/5 mm,
2
RP–phenyl). The mobile phase was acetonitrile/H O (60 : 40,
ꢀ1
v/v) at a flow rate of 1.0 mL min , and all runs were monitored
at 355 nm.
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3
. Results and discussion
The TATB structures were fabricated by the reverse micelle/
microemulsion system, AOT/water/toluene, by which many
nanostructures of inorganic compounds have been successfully
26
produced. Here we describe in detail how this system can be
extended to synthesize TATB micro/nanostructures. In order to
investigate whether pure TATB could be obtained by this
microemulsion system, X-ray powder diffraction (XRD)
measurements were carried out. Fig. 2 (bottom) shows a typical
XRD pattern of the as-resulting sample obtained at 18 h with
a molar ratio (defined as w) of water to AOT of 5. All diffraction
peaks can be assigned to a TATB phase (JCPDS No. 44-1627)
without any indication of other crystalline byproducts. It can be
seen that the pure TATB can be obtained by using urea as an
aminating agent.
To further investigate the composition of the above TATB
sample, Fourier transform infrared (FT-IR) spectroscopy was
carried out. For comparison, FT-IR spectra were taken of the as-
synthesized TATB and a commercial sample. As shown in Fig. 3,
the FT-IR spectrum of the as-synthesized TATB is in good
agreement with that of commercial one. The bands at 3320.9 and
Fig. 3 FT-IR spectra of the as-obtained twinned TATB nanobelts
(
bottom) and commercial TATB micropowders (top).
(HPLC), as shown in Fig. 4. It can be clearly seen that the HPLC
retention times of the twinned nanobelts match well with those
for standard TATB, and no other absorption peaks are observed,
indicating that no impurities of incomplete amination exist in the
sample. Also, the purity of the twinned TATB nanobelts is
calculated to be higher than 94% by comparing their peak area
with that of the reference substance, confirming that the pure
product could be obtained by the method used here.
ꢀ1
3
221.1 cm are characteristic of the asymmetrical and symmet-
rical stretching vibrations of N–H. Compared with the corre-
ꢀ1
sponding values of 3440 and 3360 cm for these bands in aniline,
the bands shift too much, pointing to the fact that there exists
very strong hydrogen bonding between the amino and nitro
ꢀ1
groups of TATB. The bands at 1570.7 and 1223.6 cm can be
ascribed to the asymmetrical and symmetrical N–O stretching
Fig. 5 displays field emission scanning electron microscopy
(FE-SEM) images of the above TATB sample obtained with a w
value of 5. A low magnification FE-SEM image is given in Fig. 5a
and shows that the sample almost completely consists of a one
dimensional ribbon-like structure with a relatively uniform width
of 2–5 mm over the entire length and a length in the range of 120
to 150 mm. However, when we magnify each ribbon, it is inter-
esting to find, as shown in Fig. 5b, that each ribbon has a distinct
grain boundary along the direction parallel to the growth
direction, confirming its twinned bi-crystal nature. The clear
grain boundary of the bi-crystal is further observed (marked by
ꢀ
1
vibrations, whereas the bands at 1615.2 and 779.6 cm are
typical of the C–N stretch of the amino groups. In addition, the
0
ꢀ1
band at 1321.6 cm is interpreted as the C–N stretch for the
ꢀ1
nitro groups and three bands at 1448.3, 1178.0, and 1031.8 cm
are attributed as the skeletal stretching modes of the aromatic
ring. The results of the FT-IR further prove the composition of
the as-obtained TATB.
The composition and purity of the as-obtained sample are
further analyzed via high performance liquid chromatography
Fig. 2 XRD patterns of the samples harvested at different reaction
Fig. 4 HPLC of the as-prepared twinned TATB nanobelts (top) and
times.
purified TATB (bottom).
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Fig. 5 FE-SEM images of the as-prepared TATB sample at (a) lower
magnification and (b) higher magnification; (c) FE-SEM image of a single
twinned nanobelt, inset shows the thickness of the nanobelt; (d) FE-SEM
of a broken nanobelt.
an arrow) in a higher magnification SEM image, as shown in
Fig. 5c, which also shows that the bi-crystal possesses a smooth
surface. The thickness of the bi-crystal is determined to be
Fig. 6 (a) TEM of the top of a single nanobelt, (b) TEM of the bottom of
a single nanobelt, (c) and (d) schematic illustration of twinned TATB
nanobelts, (e) SAED pattern of nanobelts.
2
50 nm from the SEM image (inset in Fig. 5c). Furthermore, it
can be clearly seen from a higher magnification FE-SEM image
(
Fig. 5b) that the ribbon is highly symmetrical with a wedge-
ꢁ
It was found in our experiments that the molar ratio (w value)
between water and AOT has a significant effect on the
morphology and size of the final product. Fig. 7 shows the SEM
images of the samples obtained when the concentration of urea
shaped tip with an angle of about 135 . In addition, the ribbons
are easy to rupture, as shown in Fig. 5d, and the broken ribbon
still has a wedge-shaped tip, indicating that the twinned nano-
belts break along the ab plane because of the weak bonds
between sheets, as shown in Fig. 1a.
ꢀ1
(
C ¼ 6 mol L ) and reaction time (t ¼ 18 h) are kept constant,
but the w value is adjusted to 5, 10, and 15. With w ¼ 5, many
twinned nanoribbons with an average length of 120–150 mm and
width of 5 mm (Fig. 5a) were formed. When the w value was
increased to 10, the product also contained twinned nano-
ribbons, but with an average length of about 80 mm and width of
To further reveal the structural properties, transmission elec-
tron microscopy (TEM) and selected area electron diffraction
(
SAED) were carried out. The twinned nanobelts are carefully
examined via TEM because of their poor thermal stability.
Fig. 6a and 6b depict TEM images of the top and bottom of
a TATB nanobelt with a single twin structure, respectively. It can
be clearly seen from the bottom and top of the twinned nanobelt
that each single nanobelt exhibits a quadrangle and one of the
ꢁ
angles is 109 , which is almost completely in agreement with the
ꢁ
a value (108.59 ) of the cell parameters of TATB (PDF No. 44-
1
627). So, the twinned nanobelts could be illustrated schemati-
cally by Fig. 6c. Here, the ‘‘twin’’ reflections are indexed with
a subscript ‘‘T’’ and the remaining matrix reflection indices are
marked without a subscript. Combining this morphology feature
with the crystal structure of TATB (Fig. 1) it can be deduced that
each nanobelt grows along the c-axis direction, i.e. [001] direction
(
Fig. 6d) and shares a common twin plane with the other
nanobelt. In addition, the SAED pattern exhibits a set of
diffraction dots, which correspond to the (001), (002), and (003)
crystal planes, respectively. This result on the one hand proves
the layered structure of the nanobelts and on the other hand
further confirms the growth direction of [001] for each nanobelt
(
Fig. 6e). Unfortunately, high-resolution TEM (HRTEM) is not
possible due to the poor thermal stability of TATB, and as
a result the symmetrical mirror structure at the twin boundary
can not be directly verified in the twinned nanobelts.
Fig. 7 SEM images of samples obtained at different w values of (a) 10,
ꢀ
1
(b) 15 and with different concentrations of urea of (c) 8 mol L , (d)
ꢀ
1
4 mol L
.
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about 4 mm (Fig. 7a), which are smaller than the above case. With
the w value further increased to 15, the product was composed of
only microspheres with an average diameter of less than 1 mm
The evolution of relative intensity implies that the products
harvested at different times may have a differently preferred
growth direction, which may result in the transition of
morphology of TATB crystals. More importantly, investigations
into replacing urea with an aminating agent, such as ammonia
(Fig. 9a and b), and ammonium carbonate (Fig. 9c and d),
further validated the important role of the hydrolysis of urea in
the formation of TATB twinned nanobelts.
(
Fig. 7b). Furthermore, keeping other parameters constant, we
also studied the effect of the concentration of urea. When the
ꢀ1
concentration of urea is adjusted to 8 mol L , the morphology of
the as-synthesized product consisted of wedge-shaped
nanoribbons (Fig. 7c). After decreasing the concentration to
ꢀ1
4
mol L , the product was composed of leaves (Fig. 7d). These
Up to now, significant progress has been made in the synthesis
of various inorganic twinned nanostructures in the past years,
results demonstrate that different shapes and sizes of TATB can
be obtained controllably by simply changing the w value and the
concentration of urea.
8,9,12,13
most of which exhibit a twinned zigzag structure.
For the
inorganic twinned nanostructures, twinned bi-crystals are always
divided into the categories of growth twins, gliding twins, and
transformation twins, among which growth twinning is the most
In order to investigate the growth process of twinned TATB
nanobelts, time-dependent experiments were carried out. The
ꢁ
27
samples were prepared at a constant temperature (T ¼ 90 C) and
common formation type. An agreement has been reached
ꢀ1
concentration of urea (C ¼ 6 mol L ) but with t ¼ 6, 10, 14, and
regarding the possible formation mechanism of growth twins
which is caused by an accidental departure from equilibrium
during the growth process, and favored in the nuclear stage,
especially under some critical growth conditions, such as
1
8 h, respectively. When the reaction time is 6 h, leaf-like TATB
structures are formed (Fig. 8a and b). The leaf has a length in the
range of 10–25 mm and width of 5–15 mm, and most of the leaves
have a clear vein, as marked by an arrow. If the reaction time was
further prolonged, the leaves became longer accordingly. A SEM
image of the product after a reaction time of 10 h, as shown in
Fig. 8c and 8d, reveals that the product mainly consists of
banana leaf-like structures with a length of tens of micrometres
and the width of the veins is about 4 mm, while after heating for
2
8
temperature fluctuations,
spatially separated changeable
13
29
chemical environments, and supersaturation. For example,
7
for the formation of bi-crystalline Zn P and Cd P nanobelts,
3 2
3
2
the presence of impurities could induce a lot of strains in the
initial stage, which then are accumulated gradually during the
following growth, and finally bi-crystal structures are formed as
a consequence the formation of stacking faults resulting from the
relaxation of strains. Significantly, the presence of these defects is
necessary for stabilizing the surfaces with higher energies, leading
to anisotropic growth of the one-dimensional nanostructures
1
4 h, the nano-banana leaves broke into veins, i.e. twinned
nanocrystals (Fig. 8e and f). Finally, the perfect twinned nano-
belts without other shapes are formed at 18 h (Fig. 5 and 6). The
XRD patterns of the samples with increasing reaction time
ꢁ
clearly prove the pure TATB phase with space group P1 from
30
along a specific direction.
leaf-like structures to final nanobelts, as shown in Fig. 2.
In the present study, we chose TATB as a target molecule to
grow twinned nanostructures. To the best of our knowledge,
such a perfect organic twinned nanostructure has rarely been
reported to date. As is well known, there exist abundant
hydrogen bonds in TATB, which forms a triclinic but centro-
symmetric structure. Disorder in the stacking of these sheets is
common, which may be the main contributor for the formation
31
of twinned nanostructures. Also, we emphasize the role of the
urea as an aminating agent and the microemulsion system in the
Fig. 8 SEM images of samples prepared with different reaction times
Fig. 9 SEM images of samples acquired with other aminating agent
(a, b) 6 h, (c, d) 10 h, (e, f) 14 h.
(a, b) NH
3
$H
2
O, (c, d) (NH
4 2 3
) CO .
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662 | CrystEngComm, 2011, 13, 6658–6664
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synthesis of nanostructured TATB bi-crystals. On the basis of
the above SEM and TEM analysis, we deduce that twinned
TATB nanobelt formation proceeds through four steps in the
microemulsion system, as shown in Fig. 10. This process mainly
includes: (1) nucleation and growth: urea is hydrolyzed slowly to
form CO
2
and NH
4
OH (eqn (1)), then NH
4
OH subsequently
decomposes into NH
3
and H O (eqn (2)), and finally, TATB is
2
formed by the aminating process of TCTNB and NH
The corresponding reactive equations are as follows:
3
(eqn (3)).
CO(NH
2
)
2
+ 3H
2
O # 2NH
4
OH + CO
2
(1)
(2)
NH
4
OH # H
2
O + NH
3
Fig. 11 DSC patterns of twinned TATB nanobelts (top) and commercial
TATB micropowders (bottom).
metastable broken nanosheets begin to be dissolved and recrys-
tallized, resulting in the final formation of perfect twinned
nanobelts. XRD pattern evolution of the samples with increasing
reaction time clearly proves that the (002) planes are dominant
for all nanoleaves of different sizes, but for the final nanobelts
obtained at 18 h, the (002) planes gradually weaken in intensity
while the (100) planes significantly strengthen.
(
3)
This growth process might be determined by the first step
because of the slow hydrolyzation of urea, which plays an
important role in the formation of the special morphology. Once
the above aminating reaction has started, TATB is formed,
which can accelerate the hydrolyzation of urea. The higher NH3
gas formation rate may result in supersaturation and destroy the
balance of the system energy for crystal growth during the stage
of nucleation. With the help of the microemulsion system, the
instability of the system energy may allow the nucleation to first
occur at some energetically favorable sites, leading to preferred
growth along two different one-dimensional directions and the
formation of twinned nanoleaves. (2) Further growth: when the
reaction is prolonged, the leaf-like structures continue to grow
symmetrically along the (100) planes due to their abundant intra-
and inter-molecular hydrogen bonds and large-sized twinned
nanoleaves can be obtained. (3) Partial break: with the further
increase of the width of the banana nanoleaves, the nanoleaves
tend to break along the boundary of the vein under the condition
of vigorous stirring, resulting in the formation of twinned
nanobelts and triangular nanosheets. (4) Dissolution and
recrystallization: with a further increase in reaction time, the
The result of differential scanning calorimetric (DSC) inves-
tigations of the as-prepared TATB twinned nanobelts is shown in
Fig. 11. The DSC pattern shows a sharp exothermic peak over
ꢁ
ꢁ
a narrow range around 361.5 C, a shift of approximately 8 C
toward lower temperature compared with TATB commercial
micropowders. From this thermal analysis, we can see that the
as-synthesized twinned nanobelts exhibit a typical size-depen-
dent thermal effect.
4. Conclusion
In summary, twinned TATB nanobelts have been synthesized in
a microemulsion system of AOT/water/toluene at low tempera-
ture and atmospheric pressure. By changing the conditions of the
reaction, we can obtain different morphologies and sizes of
TATB with good crystallinity. The powder XRD patterns, FTIR
spectra, DSC curves and HPLC analysis of the product are
utilized to confirm the TATB composition. Meanwhile, studies
on the detailed formation mechanism are underway. This simple
microemulsion-assisted wet chemical synthesis strategy may
represent a general approach for the preparation of micro/
nanostructures of other organic small-molecule materials.
Acknowledgements
This work was supported by the Natural Science Foundation of
China (NSFC, Nos. 20731002, 20871016, 10876002, 91022006
and 20973023), the 111 Project (B07012), Program for New
Century Excellent Talents in University, Open Fund of State Key
Laboratory of Explosion Science and Technology and Beijing
Institute of Technology (Nos. ZDKT08-01 and YBKT09-13),
Specialized Research Fund for the Doctoral Program of Higher
Education (SRFDP, No. 200800070015), Funding Project for
Science and Technology Program of Beijing Municipal
Commission (No. Z09010300820902), and the Key Foundation
of China Academy of Engineering Physics (No. 2009A0302017).
Fig. 10 Schematic illustration of the possible growth mechanism of
twinned TATB nanobelts.
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1
6 S. F. Son, B. W. Asay, B. F. Henson, R. K. Sander, A. N. Ali,
P. M. Zielinski, D. S. Phillips, R. B. Schwarz and C. B. Skidmore,
J. Phys. Chem. B, 1999, 103, 5434–5440.
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