A Bunch-like Copper Oxide Nanowire Array as an Efficient, Durable, and Economical Catalyst for the Methanolysis of Ammonia Borane

Article abstract of DOI:10.1002/cctc.201701317

The dehydrogenation of ammonia borane (AB) is an effective method to produce and store hydrogen, but efficient, durable, and low-costing dehydrogenation catalysts are lacking. In this work, we successfully prepared a self-supported bunch-like copper oxide

Full text of DOI:10.1002/cctc.201701317

Accepted Article
Title: Bunch-like Copper Oxide Nanowire Array as an Efficient, Durable
and Economical Catalyst for Methanolysis of Ammonia Borane
Authors: Jingquan Liu, Liang Cui, Xueying Cao, Xuping Sun, and
Wenrong Yang
This manuscript has been accepted after peer review and appears as an
Accepted Article online prior to editing, proofing, and formal publication
of the final Version of Record (VoR). This work is currently citable by
using the Digital Object Identifier (DOI) given below. The VoR will be
published online in Early View as soon as possible and may be different
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the VoR from the journal website shown below when it is published
to ensure accuracy of information. The authors are responsible for the
content of this Accepted Article.
To be cited as: ChemCatChem 10.1002/cctc.201701317
Link to VoR: http://dx.doi.org/10.1002/cctc.201701317
A Journal of
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ChemCatChem
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COMMUNICATION
Bunch-like Copper Oxide Nanowire Array as an Efficient, Durable
and Economical Catalyst for Methanolysis of Ammonia Borane
[a,b]
[b]
[c]
[b]
[a,b]
Liang Cui,
Xueying Cao, Xuping Sun, Wenrong Yang, and Jingquan Liu,*
Abstract: Dehydrogenation of ammonia borane (AB) offers an
effective method for production and storage of hydrogen but suffers
from the development of efficient, durable and low-cost
dehydrogenation catalysts. In this work, we have successfully
prepared a self-supported bunch-like copper oxide nanowire array
on copper foam (b-CuO NA/CF) through a facile in-situ wet oxidation
and anneal method. This b-CuO NA/CF shows high catalytic activity
for AB methanolysis with an initial turnover frequency of 13.3 mol(H2)
AB conversion. Up to now, various noble and non-noble based
[
19,20]
[21-23]
[12,17,24]
[25]
[25,28]
catalysts, such as Ru,
Rh,
Pd
Co, Ni,
and
[
13,27,28]
Cu,
have been widely studied for hydrogen generation
from AB methanolysis, among which the Cu species have been
regarded as the most promising ones due to its low-cost and
high catalytic activity. In 2008, Jagirdar and co-workers designed
a nanostructured Cu
more active than the Cu and Cu@Cu
catalyzing AB methanolysis reaction.
further prepared diverse mesoporous CuO nanostructures,
2
O, and found that Cu
2
O nanoparticles are
O nanopowders in
Yang and co-workers
2
-
1
-1
-1
[28]
mol (CuO) min and an activation energy of 34.7 kJ mol . Moreover,
such self-supported bunch-like nanoarray catalyst can be easily
separated from fuel solutions with excellent stability and can still
maintain its catalytic activity even after long-time uses, providing a
direct, efficient, economical and durable catalyst for hydrogen fuel
cells.
[
13]
and Kaya et al. also reported activated carbon supported Cu-
[
27]
Cu
2
O-CuO nanoparticles for AB methanolysis,
showing that
CuO is a promising catalyst in AB methanolysis reaction.
However, all these Cu-based catalysts including other metal-
based catalyst systems have powder-like structures, suffering
from easy aggregation, difficult reuse and mass loss in
continuous flow systems. Our previous works have proven that
Increasing fossil fuels consumption and environmental
concerns have greatly promoted the establishment of hydrogen
[29-31]
self-supported nanostructures could solve the above issues.
[1,2]
energy system.
3 3
Ammonia borane (AB, NH BH ) is considered
Thus, it is highly desired but still remains a great challenge to
develop an economical self-supported nanostructured Cu-based
catalyst for efficient and stable AB methanolysis for hydrogen
production.
to be a promising material for hydrogen storage and production
due to its high theoretical hydrogen capacity (19.6 wt%), low
-1
molecular weight (30.7 g mol ), good stability and safe reaction
[
3-11]
conditions.
In general, AB hydrolysis and methanolysis are
In this work, for the first time, a bunch-like CuO nanowire
array on copper foam (b-CuO NA/CF) is developed via a facile
and economical method and it behaves as an efficient catalyst
for methanolytic dehydrogenation of AB. b-CuO NA/CF exhibits
high catalytic activity for AB methanolysis with an initial turnover
two practical ways of hydrogen generation from AB for hydrogen
fuel cell vehicles, and among them the latter is more
advantageous than the former despite its lower hydrogen
[
12-14]
capacity.
Similar to AB hydrolysis, in the presence of
suitable catalyst, AB methanolysis reaction can be briefly
expressed as follows:
-1
-1
frequency (TOF) of 13.3 mol(H2) mol(CuO) min and an activation
-1
energy of 34.7 kJ mol . Moreover, this self-supported bunch-like
NH
3
BH
3
+ 4CH
3
OH
NH
4
B(OCH
3
)
4
+ 3H
2
(1)
nanoarray catalyst can be easily separated from fuel solutions
with excellent stability and can still maintain its catalytic activity
even after long-time uses.
b-CuO NA/CF was derived through a simple thermal treatment
2
of its Cu(OH) NA/CF precursor which was prepared via a facile
Compared to AB hydrolysis process, the above reaction even
can be initiated below 0 °C, thereby satisfying the applications in
[
15]
cold environment. More importantly, there is no NH
3
release in
leading to the generation of pure H . In
addition, the by-product of (NH B(OCH can be easily
reconverted into AB by reaction with LiAlH4 and NH
[
16,17]
AB methanolysis,
2
4
3 4
) )
in situ wet-oxidation treatment of copper foam (CF) at room
[
18]
4
Cl.
[32]
temperature (Figure 1a). The reddish brown copper foam was
It is well known that the catalyst plays a critical role in AB
methanolysis in determining the hydrogen generation rate and
converted to light blue after oxidation and further transformed
into black after thermal annealing at 300°C, indicating the
formation of new phase and phase transformation, respectively
(
Figure S1, ESI). Figure S2 depicts XRD patterns of bare CF,
Cu(OH) NA/CF and b-CuO NA/CF. The Cu(OH) product shows
diffraction peaks indexed to the orthorhombic phase of Cu(OH)
(JCPDF 35-0505), demonstrating the successful formation of
Cu(OH) . Following the thermal treatment, only peaks for CuO
JCPDF 48-0937) are observed except for those of bare CF
(JCPDF 04-0836), clearly indicating the complete conversion of
Cu(OH) into CuO. Scanning electron microscopy (SEM) image
[a]
[b]
[c]
Dr. L. Cui, Prof. W. Yang, J. Liu
College of Material Science and Engineering, Linyi University,
Linyin, 276000 Shandong, China
E-mail: jliu@qdu.edu.cn
X.Cao, Prof. J. Liu
College of Chemical and Environmental Engineering, Qingdao
University,
Qingdao 266071, Shandong (China)
Prof. X. Sun
College of Chemistry, Sichuan University
Chengdu 610064, Sichaun (China)
2
2
2
2
(
2
for bare CF (Figure 1b) shows that CF has a 3D cross-linked
grid structure and clean surface, which was fully covered with
Supporting information for this article is given via a link at the end of
the document.
crossed Cu(OH)
Figure 1c). Following thermal treatment, Cu(OH)
decomposed into CuO with connected tops, forming a bunch-like
2
nanowires after the wet-oxidation process
(
2
will be
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ChemCatChem
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COMMUNICATION
CuO nanowire array (Figure 1d). The energy-dispersive X-ray
before and after methanolysis process using X-ray photoelectron
spectroscopy (XPS). Particularly, the sample after catalyzing the
(
EDX) spectrum and corresponding element mapping images of
b-CuO NA/CF reveal it has a Cu:O atomic ratio of 1:1 with a
uniformly distributed elements (Figure 1e). Figure 1f presents
2
methanolysis reaction was kept in N atmosphere before
characterization. Figure 4a shows the Cu LMM region for b-CuO
NA/CF, the strong feature at 917.7 eV indicates the existence of
the transmission electron microscopy (TEM) image of Cu(OH)
2
2
+
nanowire, giving a diameter of approximately 130 nm with a
smooth surface. TEM image of CuO nanowire shows a rough
surface with a decreased diameter of about 100 nm (Figure 1g).
The selected area electron diffraction (SAED) image of CuO
nanowire reveals an almost single-crystal-like diffraction pattern.
All these observations confirm the successful fabrication of
integrated bunch-like CuO nanowire array on copper foam.
Cu , while two peaks at 916.8 and 918.6 eV appeared after
1
+
0
methanolysis which can be assigned to Cu
respectively.
and Cu ,
Figure 4b shows the Cu 2p peaks at 934.0
(2p3/2) and 953.8 eV (2p1/2) with strong statellite peaks,
[
33]
[
34,35]
indicating the existence of CuO.
However, both the two
peaks are negatively shifted after the catalyzing process to
932.2 and 952.1 eV, respectively, and the statellite peaks have
2
+
1+
also disappeared, confirming the reduction of Cu to Cu and
0
[10]
Cu by AB in the methanolysis reaction. Figure 4c illustrates
the O 1s spectra before and after the AB methanolysis process,
1
+
2+
showing the existence of Cu -O and Cu -O, proving the
[36]
reduction mechanism in catalyzing AB methanolysis.
Thus,
Cu and Cu are the real active sites for AB methanolysis in our
case and a plausible mechanism is provided to illustrate the H
generation process. As shown in Figure 4d, the b-CuO NA/CF
1
+
0
2
2
+
having Cu on its surface can interact strongly with AB forming
the activated complex which was further dissociated to generate
hydrogen when being attacked of CH
3
OH molecule to form Cu-H
2
+
bond. According to this mechanism, Cu is firstly reduced to
1
+
0
1+
Cu and Cu among which the latter is then oxidized to Cu
during
catalysis.
the
dehydrogenation
process
for
repeated
[
13,28,37]
Figure 1. (a)Illustration for the stepwise preparation of b-CuO NA/CF. (b-d)
SEM images of bare CF, Cu(OH)
elemental mapping of b-CuO NA/CF and its corresponding SEM image. (f)
TEM image of single Cu(OH) nanowire and (g) TEM images of single CuO
2
NA/CF and b-CuO NA/CF (e) EDX
2
nanowire and its corresponding SAED pattern.
We studied the catalytic activity of bare copper foam, Cu(OH)
2
NA/CF and b-CuO NA/CF for hydrogen generation via AB
methanolysis. It is very interesting to have found that vigorous
bubbles occur for Cu(OH) NA/CF and b-CuO NA/CF in AB
2
methanol solution (Figure S3a). Besides, bare CF shows almost
no activity towards AB methanolysis. Thus, the copper oxides
1
+
2+
[25]
(
Cu or Cu ) are the active species for AB methanolysis.
water displacement equipment was designed to measure the
insight activities of bare copper foam, Cu(OH) NA/CF and b-
A
2
CuO NA/CF in the catalytic methanolysis of AB. As shown in Fig.
S3b, b-CuO NA/CF exhibits the best catalytic activity (45%
conversion in 5 min) which slows down continuously with the
decreasing AB concentration as the reaction proceeds.
Figure 2. (a-c) Cu LMM, Cu 2p and O 1s XPS spectra of b-CuO NA/CF before
blue) and after (red) catalyzing AB methanolysis reaction; (d) The proposed
mechanism of b-CuO NA/CF in catalyzing the methanolysis of AB for
hydrogen generation.
(
Interestingly, the catalytic activity for Cu(OH)
more rapidly than that of b-CuO NA/CF, which can be due to the
collapsed Cu(OH) nanowires after the methanolysis process
Figure S4a and b). In sharp contrast, b-CuO NA/CF can
maintain its nanoarray structure during the catalytic process
Figure S4c and d), leading to the higher catalytic activity and
stability.
To obtain more insight into the active sites, we explore the
different valence states of Cu and O elements in b-CuO NA/CF
2
NA/CF decreased
A kinetic study was performed to gain further insight into the
catalytic activity of b-CuO NA/CF for hydrogen generation from
AB methanolysis. Figure 3a shows the plots of volume of
hydrogen versus time under various CuO/AB molar ratios with a
fixed amount of AB (0.6 mmol, 3 mL) at room temperature. It
suggests that when the catalyst content increased, the reaction
2
(
(
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COMMUNICATION
respectively. It can be seen that the HGR increased with the
increased AB concentrations, giving a final AB conversion of
approximately 92.1% (Figure 3c). Particularly, the reaction is
nearly half-order with respect to the AB concentration (Figure
3
d) due to the Cu cations re-reduction during the methanolysis
[19,39,40]
process, which is similar to other Cu-based catalysts.
a
The methanolysis activation energy (E ) was evaluated by
measuring the hydrogen evolution capability at different
temperature. Figure 3e shows the temperature-dependent
hydrogen generation of the b-CuO NA/CF catalyst from 293 to
308 K. As observed, HGR increased dramatically at higher
temperature, which should be due to the accelerated movement
of AB and methanol molecules, leading to increasing number of
[
41]
effective collision that passes the threshold energy barrier.
However, the final AB conversion remains almost constant
under high temperatures(>298K). From the slop of the straight
-1
a
line in Figure 3f, E was calculated to be 34.7 kJ mol for AB
methanolysis reaction using Arrhenius equation (experimental
section for details). This value compares favourably to those of
2
many other Cu-based catalysts, such as Cu-Cu O-CuO/C (67.9
-1
[27]
-1 [13]
kJ mol ) and CuO powder (34.2 ± 1.2 kJ mol ) and even
lower than those of other noble and non-noble metal catalysts as
listed in Table 1. The high catalytic activity of b-CuO NA/CF can
be attributed to its nanowire structures, which expose more
active sites and facilitate mass transfer during methanolysis
process.
2
Figure 3. (a) Plots of mol H evolved per mol of AB versus time for the
methanolysis of AB in methanol solution containing fixed amount of of AB (0.6
mmol) in the presence of b-CuO NA/CF with various CuO/AB molar ratios at
a 3 3
Table 1 Comparison of E and TOF for the methanolysis of NH BH using
298 K and (b) its corresponding logarithmic plot of HGR versus [CuO]; (c)
various catalysts.
Plots of mol H evolved per mol of AB versus time for the methanolysis of AB
2
at fixed CuO amount (0.017 mmol) with different AB concentrations at 298 K
and (d) its corresponding logarithmic plots of HGR versus [AB]; (e) Plots of
-
-
Catalyst
E
)
a
(kJ mol
TOF (min
)
T (K)
Ref
1
1
mol H
2
evolved per mol of AB versus time for the methanolysis of AB in the
([CuO]/[AB] 0.018) and its
mL fuel solution was applied for each
presence of b-CuO NA/CF at 298-308
corresponding Arrhenius plot.
experiment.
K
=
3
Rh/SiO
2
62
56
168
147
118.1
99.4
66.9
65.5
53.2
49.1
27.7
24
298
[22]
[23]
[19]
[20]
[42]
[21]
[24]
[39]
[12]
[27]
[17]
Rh/nanoHAP
Ru/MMT
298
298
298
298
298
298
298
298
298
298
298
298
293
293
298
293
298
298
23.8
54.1
58
Ru/graphene
PVP-stabilized Ru
Rh/CC3-R-hetro
CuPd/C
time for generating hydrogen (60% conversion) decreased
-
obviously from 20 to 5.3 min. Hydrogen generation rate (mL min
)
NG
NG
24.4
25
1
is calculated from the initial stage of each plot (experimental
section for details), and the obtained logarithmic plot shows a
slop of 0.87 which is close to 1.0 (Figure 3b). This result
indicates that the catalytic methanolysis of AB is first order with
respect to the CuO concentration, which is similar to the reports
CuNi/graphene
CoPd/C
Cu-Cu
2
O-CuO/C
67.9
35
PVP-stabilized Pd
b-CuO NA/CF
PVP-stabilized Ni
Co-Ni-B
22.3
13.3
12.1
10
[
13,19,27,38,39]
by others.
The highest initial turnover frequency (TOF)
34.7
63
This work
[27]
was obtained at CuO/AB molar ratio of 0.01, which is calculated
-1
-1
2
to be 13.3 mol(H ) mol (CuO) min . Though this value is not
NG
NG
40
[25]
the highest one ever reported for the methanolysis of AB using
various catalysts as listed in Table 1, it is still higher than many
other relevant catalyst systems, such as PVP-stabilized Ni (12.1
Co-Co
2
B
7.5
[25]
Rh/zeolite
6.3
[38]
Ni-Ni
CoCl
NiCl
3
B
NG
NG
NG
5
[25]
-
1
-1
min ), Co-Ni-Bi (10 min ) and nanostructured CuO powder
(
2
3.7
[18]
-1
2.41 min ). Those methanolysis catalysts with higher TOF than
that of b-CuO NA/CF are either noble-metal (Rh, Ru and Pd)
based systems or powder-like catalysts (Cu-Cu O-CuO/C and
2
2.9
[18]
Nanostructured
CuO
34.2
2.41
298
[13]
2
CuNi/graphene) which should be deposited onto substrate in the
application of hydrogen fuel cells.
In another group of tests, CuO amount was fixed at 0.017
mmol but the AB was varied from 0.3-1.2 mmol. The kinetic and
corresponding logarithmic plots are given in Figure 3c and d,
Pd/C
NG
NG
NG
NG
NG
2.0
1.6
298
298
298
298
298
[18]
[18]
[28]
[28]
[28]
PdCl
Cu
2
2
O
0.21
0.16
0.12
Nano Cu@Cu
2
O
Nano Cu
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ChemCatChem
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COMMUNICATION
In flow fuel systems for practical applications, controllability
and stability are vital for the dehydrogenation catalyst. Such self-
supported b-CuO NA/CF catalyst can offer more advantages
(Shanghai, China). Hydrochloric acid (HCl) and methanol were
purchased from Tianjin Fuyu Ltd.. All the reagents were used as received.
The ultrapure water used throughout all experiments was prepared
through a FLOM water purified system.
[29,30,43]
than traditional powder catalyst systems in this respect.
As shown in Figure 4a, the methanolysis process can be well
controlled by b-CuO NA/CF. When the catalyst, b-CuO NA/CF
Preparation o Preparation of Cu(OH)
Cu(OH) NA/CF)
2
nano array on copper foam
(
2
(
ON) was separated from fuel solution, the reaction stopped
quickly (OFF); while in the presence of catalyst hydrogen
release occurs immediately with almost the same rate,
demonstrating good sensitivity and stability of b-CuO NA/CF to
AB methanolysis. The recyclability of b-CuO NA/CF catalyst was
also examined in the methanolysis of AB (Figure 4b). It can be
seen that the HGR (slop of the line) is constant even after seven
cycles of repeated uses and the final conversion remains almost
the same for each cycle, indicating a stable catalytic activity and
good recyclability of b-CuO NA/CF in AB methanolysis. The
remarkable durability for b-CuO NA/CF could be attributed to its
unique bunch-like nanostructure, which is more stable than
separate nanowires and nanopowders.
2
A piece of Cu foam (2 × 2 cm ) was pretreated with hydrochloric acid and
washed with water and ethanol several times to ensure the surface of the
copper foam was well cleaned before use. The pretreated copper foam
was immersed into a 30 mL aqueous solution containing 4 mmol
(NH
the sample was taken out and washed with pure water and ethanol
several times and then dried in air at room temperature (Cu(OH) loading
4 2 8
)S O and 80 mmol NaOH at room temperature for 20 min. After that,
2
-
2
=
0.72 mg cm )
.
Preparation of bunch-like CuO nanoarray on copper foam (b-CuO
NA/CF)
b-CuO NA/CF was prepared through
annealing treatment of the above Cu(OH)
obtained Cu(OH)
a
facile and simple thermal
NA/CF. Typically, the above
2
2
NA/CF was put into a porcelain boat in a furnace and
-
1
heated to 300 °C with a heating rate of 5 °C min and held at this
temperature for 2 h. CuO loading amount was obtained via inductively
coupled plasma mass spectrometry (ICP-MS) analysis, in which CuO
was dissolved by acetic acid, .and the result was calculated to be 0.65
-
2
mg cm .
Characterizations
X-ray diffraction (XRD) data were acquired on a RigakuD/MAX 2550
diffractometer with Cu Kα radiation (λ=1.5418 Å). SEM measurements
were made on a HITCHI S-4800 with scanning electron microscope at an
accelerating voltage of 20 kV. Transmission electron microscopy (TEM)
images were taken on a HITACHI H-8100 electron microscopy (Hitachi,
Tokyo, Japan) at 200 kV. X-ray photoelectron spectrometer
measurements (XPS) were performed on an ESCALABMK II using Mg
Figure 4. (a) Plots of mol H
controllability test of b-CuO NA/CF in AB methanolysis reaction; (b) Plots of
mol H evolved per mol of AB versus time for b-CuO NA/CF catalyzed
methanolysis of AB. (0.6 mmol AB, 0.017 mmol CuO, 3 mL fuel solution was
applied for each experiment at 298 K).
2
evolved per mol of AB versus time for the
2
as the exciting source, and b-CuO NA/CF sample was kept in N
2
In summary, a bunch-like CuO nanowire array on copper foam
b-CuO NA/CF) was developed as an efficient and stable
atmosphere after methanolysis process before characterization. ICP-MS
analysis was performed on Thermo Scientific iCAP6300.
(
catalyst for AB methanolysis for hydrogen generation via a
simple oxidation process. This method is facile, scalable and
economical, and the as-prepared b-CuO NA/CF exhibits high
catalytic activity for AB methanolysis with an initial turnover
Hydrogen generation measurement
The volume of hydrogen was measured using water displacement
method. Typically, the methanolytic dehydrogenation experiments were
performed in a 25 mL two-necked round-bottom flask with one neck
connected to a gas burette and the other sealed with a rubber cap. The
temperature of the reaction system was kept at the desired value by
-1
-1
frequency (TOF) of 13.3 mol(H2) mol(CuO) min and an activation
-1
energy of 34.7 kJ mol . Furthermore, b-CuO NA/CF can be
easily separated from fuel solutions and has excellent stability
due to its unique bunch-like nanowire structure. Moreover, such
self-supported bunch-like nanoarray catalyst can be easily
separated from fuel solutions with excellent stability and can still
maintain its catalytic activity even after long-time uses, providing
a direct, efficient, economical and durable catalyst for hydrogen
fuel cells.
3 3
using a constant temperature bath. b-CuO NA/CF was put into NH BH
methanol solution in the two-necked round-bottom flask and the volume
of displaced water was automatically calculated using an electronic
balance (SHIMADZU, AUW220D, d = 0.01 mg) connected to a computer
(Figure S5). The systematic and personal error can be substantially
reduced in such a way. The catalytic activity of b-CuO NA/CF can be
expressed with three parameters, hydrogen generation rate (HGR, mL
-
1
-1
-1
2
min ), turnover frequency (TOF, mol(H ) mol (CuO) min ) and
activation energy. The corresponding calculating formulas are as follow:
Experimental Section
V
퐻퐺푅 =
t
Materials
P
Copper foam was purchased from Jiangsu Jiayisheng Foam Metal Co.,
Ltd. NH BH , (NH ) S O , and NaOH were bought from Aladdin Ltd.
3 3 4 2 2 8
푇푂퐹 =
× 퐻퐺푅
nRT
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ln(푇푂퐹) = ln 퐴 −
ChemCatChem
10.1002/cctc.201701317
COMMUNICATION
퐸푎
[28]
S. B. Kalidindi, U. Sanyal, B. R. Jagirdar, Phys. Chem. Chem. Phys.,
2009, 40, 5870-5874.
RT
[
[
[
[
[
[
29] L. Cui, X. Sun, Y. Xu, W. Yang, J. Liu, Chem.-Eur. J., 2016, 22, 14831-
4835.
30] L. Cui, Y. Xu, L. Niu, W. Yang, J. Liu, Nano Research, 2017, 10, 595-
04.
31] Y. Huang, K. Wang, L. Cui, W. Zhu, A. M. Asiri, X. Sun, Catal. Commun.,
016, 87, 94-97.
32] J. Tian, Q. Liu, N. Cheng, A. M. Asiri, X. Sun, Angew. Chem. Int. Ed.,
014, 53, 9577-9581.
33] S. Ikeda, K. Akamatsu, H. Nawafune, J. Mater. Chem., 2001, 11, 2919-
921.
34] Chastain, J., Ed. Handbook of X-Ray Photoelectron Spectra:
3
where V (m ) is the volume hydrogen which can be obtained from the
1
5
volume of drained water; t (min) is the corresponding time; P (1.01×10
Pa) is the standard atmospheric pressure; n is the mole of CuO; R is a
constant (8.314 J K mol ); A is the pre-experimental factor and T (K) is
the absolute temperature.
6
-
1
-1
2
2
Acknowledgements
2
A
This work was supported by Qingdao Innovation Leading Expert
Program, and Qingdao Basic & Applied Research project (15-9-
Reference Book of Standard Spectra for Identification; Perkin Elmer:
Eden Prairie, MN, 1992.
1
-100-jch).
[
[
35] H. Ang, W. Zhang, H. T. Tan, H. Chen, Q. Yan, J. Power Sources, 2015,
2
94, 377-385.
36] Y. Wang, Y. Lü, W. Zhan, Z. Xie, Q. Kuang, L. Zheng, J. Mater. Chem. A,
015, 3, 12796-12803.
Keywords: bunch-like nanostructure • CuO nanocatalyst •
ammonia borane • methanolysis • hydrogen
2
[
[
37] Q. Xu, M. Chandra, J. Power Sources, 2006, 163, 364-370.
38] S. Çalışkan, M. Zahmakıran, S. Özkar, Appl. Catal. B-Environ,, 2010, 93,
[
1]
M. Jacobson, W. Colella, D. Golden, Science, 2005, 308, 1901-1905.
3
87-394.
39] C. Yu, J. Fu, M. Muzzio, T. Shen, D. Su, J. Zhu, S. Sun, Chem. Mater.,
017, 29, 1413-1418.
[
[
2]
3]
M. Yadav, Q. Xu, Energy Environ. Sci., 2012, 5, 9698-9725.
U. Sanyal, U. B. Demirci, B. R. Jagirdar, P. Miele, ChemSusChem, 2011,
[
[
[
[
2
4
, 1731-1739.
O. n. Metin, V. Mazumder, S. Ozkar, S. Sun, J. Am. Chem. Soc., 2010,
32, 1468-1469.
40] C. Y. Peng, L. Kang, S. Cao, Y. Chen, Z. S. Lin, W. F. Fu, Angew. Chem.
Int. Ed., 2015, 54, 15951-15955.
[
4]
1
41] J. Mahmood, S.-M. Jung, S.-J. Kim, J. Park, J.-W. Yoo, J.-B. Baek,
Chem. Mater., 2015, 27, 4860-4864.
[
[
5]
6]
L. Schlapbach, A. Züttel, Nature, 2001, 414, 353-358.
H.-L. Jiangꢀ, S. K. Singhꢀ, J.-M. Yanꢀ, X.-B. Zhang, Q. Xu,
ChemSusChem, 2010, 3, 541-549.
42] H. Erdoğan, Ö. Metin, S. Özkar, Catal. Today, 2011, 170, 93-98.
[
43] P. Krishnan, S. G. Advani, A. K. Prasad, Appl. Catal. B-Environ, 2009,
6, 137-144.
[
7]
A. Bulut, M. Yurderi, İ. E. Ertas, M. Celebi, M. Kaya, M. Zahmakiran,
Appl. Catal. B-Environ, 2016, 180, 121-129.
8
[
[
8]
9]
W. Zhan, Q. L. Zhu, Q. Xu, ACS Catal., 2016, 6, 6892-6905
C. Wang, J. Tuninetti, Z. Wang, C. Zhang, R. Ciganda, L. Salmon, S.
Moya, J. Ruiz, D. Astruc, J. Am. Chem. Soc., 2017, 139, 11610-11615.
[
[
10] D. Özhava, S. Özkar, Mol. Catal., 2017, 439, 50-59.
11] Y. Liu, J. Zhang, H. Guan, Y. Zhao, J.-H. Yang and B. Zhang, Appl. Surf.
Sci., 2018, 427, 106-113.
[
[
[
[
[
[
12] D. Sun, V. Mazumder, O. n. Metin, S. Sun, ACS Catal., 2012, 2, 1290-
1295.
13] Q. Yao, M. Huang, Z.-H. Lu, Y. Yang, Y. Zhang, X. Chen, Z. Yang,
Dalton Trans., 2015, 44, 1070-1076.
14] X. Ma, Y.-X. Zhou, H. Liu, Y. Li, H.-L. Jiang, Chem. Commun., 2016, 52,
7
719-7722.
15] C. T. F. Lo, K. Karan, B. R. Davis, Ind. Eng. Chem. Res., 2007, 46,
478-5484.
16] A. Brockman, Y. Zheng, J. Gore, Int. J. Hydrogen Energy, 2010, 35,
350-7356.
17] H. Erdoğan, Ö. Metin, S. Özkar, Phys. Chem. Chem. Phys., 2009, 11,
0519-10525.
5
7
1
[
[
18] P. V. Ramachandran, P. D. Gagare, Inorg. Chem., 2007, 46, 7810-7817.
19] H. B. Dai, X. D. Kang, P. Wang, Int. J. Hydrogen Energy, 2010, 35,
1
0317-10323.
20] S. Peng, J. Liu, J. Zhang, F. Wang, Int. J. Hydrogen Energy, 2015, 40,
0856-10866.
21] J. K. Sun, W. W. Zhan, T. Akita, Q. Xu, J. Am. Chem. Soc., 2015, 137,
063-7066.
[
[
1
7
[
[
[
22] D. Özhava, S. Özkar, Appl. Catal. B-Environ, 2016, 181, 716-726.
23] D. Özhava, S. Özkar, Int. J. Hydrogen Energy, 2015, 40, 10491-10501.
24] P. Li, Z. Xiao, Z. Liu, J. Huang, Q. Li, D. Sun, Nanotechnology, 2015, 26,
025401..
[
[
[
25] S. B. Kalidindi, A. A. Vernekar, B. R. Jagirdar, Phys. Chem. Chem.
Phys., 2009, 11, 770-775.
26] D. Özhava, N. Z. Kılıçaslan, S. Özkar, Appl. Catal. B-Environ, 2015, 162,
573-582.
27] M. Yurderi, A. Bulut, I. E. Ertas, M. Zahmakiran, M. Kaya, Appl. Catal. B-
Environ, 2015, 165, 169-175.
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ChemCatChem
10.1002/cctc.201701317
COMMUNICATION
COMMUNICATION
Liang Cui, Xueying Cao, Xuping Sun,
Wenrong Yang, and Jingquan Liu *
Page No. – Page No.
Bunch-like Copper Oxide Nanowire
Array as an Efficient, Durable and
Economical Catalyst for Methanolysis
of Ammonia Borane
Bunch-
like CuO nanowire array on copper foam (b-CuO NA/CF) is obtained via a
facile and economical method and behaves as an efficient and durable catalyst
for hydrogen generation from controlled methanolysis of ammonia borane.
This article is protected by copyright. All rights reserved.