A 3D dendritic WSe2 catalyst grown on carbon nanofiber mats for efficient hydrogen evolution

Article abstract of DOI:10.1039/c5ta02538a

3D dendritic WSe₂ on conductive carbon nanofiber mats (d-WSe₂/CFM) was designed and synthesized by a diffusion-controlled CVD method. The d-WSe₂/CFM was directly used as a cathode for the HER. The substantially improved HER performance is ascribed to the novel 3D structure with effectively exposed edge sites.

Full text of DOI:10.1039/c5ta02538a

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D dendritic WSe catalyst grown on carbon nanofiber mats for
2
efficient hydrogen evolution
Received 00th January 20xx,
Accepted 00th January 20xx
a,1
b,1
a
a,*
b,**
a
MeiLing Zou, JubnFeng Zhang, Han Zhu, MingLiang Du, QingFa Wang, Ming Zhang,
XiangWen Zhang
DOI: 10.1039/x0xx00000x
www.rsc.org/
3
D dendritic WSe
WSe /CFM) was designed and synthesized by
controlled CVD method. The d-WSe /CFM was directly used as WSe
2
on conductive carbon nanofiber mats (d- WSe
diffusion- far as we know, it is still of great challenge to control the growth of
. In our previous study, the hierarchical structural TMDs were
2
with the aim at enhancing its HER performance. However, as
2
a
2
2
cathode for HER. The substantially improved HER performance are assembled on electrospun carbon nanofibers substrate, exhibiting
ascribed to the novel 3D structure with effectively exposed edge excellent performance in electrochemical hydrogen evolution
2
2-24
sites.
applications.
This communication will provide a more efficient
electrode for
and facile approach to construct hierarchical WSe
2
Electrocatalytic production of hydrogen from water splitting
has been developed as an effective approach for reducing our
HER with both high effective density of edge sites and high
conductive carbon nanofiber mat substrate for HER.
1
,2
reliance on hydrocarbon fuels.
Various catalysts have been
According to classical crystal growth theory, dendritic growth,
layer-by-layer (LBL) growth and screw-dislocation-driven (SDD)
3
-5
investigated for hydrogen evolution reactions (HER). Although
platinum (Pt) or doped Pt catalyst are found to be highly active, the
2
5
growth are the three basic growth types. Generally, a high
supersaturation condition is required for both dendritic growth and
6
-8
high cost heavily impedes its wide application in a large scale.
Therefore, a number of alternative catalysts, such as transition
2
6,27
LBL growth.
SDD growth is much more favorable at lower
2
8,29
metal dichalcogenides (TMDs) MX (M=Mo, W and X=S, Se), are
2
supersaturation than former ones.
Under conditions where a
being extensively studied since their electrocatalytic activities were
rough interface is assumed, such as high supersaturation, the
crystal is bounded by rounded noncrystallographic interfaces. If
morphological instability occurs on such a rough interface, the
9
-12
identified.
Both experimental and computational studies has
highlighted that the HER activity of TMDs correlates with the active
1
3
25
edge sites, consequently, hierarchically constructing TMDs with
high edge fraction is of high importantance to improve HER
crystal takes dendritic form. The generated structure via dendritic
growth can, thus, be fully dominated by changing the vapor
concentration in chemical vapor deposition (CVD) process.
performance. For example, the density of edge sites of 2H MoS is
2
highly addressed since it dominates the HER activity while the basal
In this study, we proposed a method to synthesize 3D dendritic
WSe2 with carbon nanofiber mats (CFM) as the conductive
substrate by using CVD method. In this method, the diffusion flux of
Se vapor inversely depends on the lateral distance away from the
1
4-16
plane is believed to be inert.
As one of the most promising
TMDs, WSe has been investigated in the fields of batteries, field-
2
1
7-20
effect transistors, diode, and so on.
Recently, the study on WSe2
3
0
for HER are given on rational design of WSe catalyst with more
2
left edge of the furnace. At the upsteam of the furnace, the Se
vapor concentration is supersaturated, then a rough reaction and
growth interface is constructed, leading to morphological instability
occurs on such a rough interface, resulting in the formation of WSe2
nanostructure with dendritic crystal structure. However, at the
downsteam, rose-like WSe2 nanostructure formed due to the
reduced driving force caused by the much lower Se vapor
exposure of active edge sites and the resluts shows that
nanostructured WSe is also a promising and appealing HER
2
12,21
electrocatalyst.
These results motivate us to design hierarchical
a.
Key Laboratory of Advanced Textile Materials and Manufacturing Technology of
the Ministry of Education, College of Materials and Textile, Zhejiang Sci-Tech
University, 310018, P. R. China
concentration. Therefore, the WSe nanosheet growth is subject to
2
b.
Key Laboratory for Green Chemical Technology of the Ministry of Education,
School of Chemical Engineering and Technology, Tianjin University, 92 Weijin
Road, Tianjin, 300072, P. R. China
strong influences of the diffusion of Se vapor through the boundary
layer of Ar gas flows. Finally, the generated structures are tailored
by the diffusion controlled concentration of Se vapor.
†
Electronic supplementary information (ESI) available: Experimental details. the
EDS analysis and optical image of d-WSe
TS-WSe -CFM. XRD and Raman characterizations of d-WSe
Photo of the working electrode for d-WSe /CFM. The magnified SEM images of
CFM and WO /CFM. CV plots of d-WSe /CFM electrode at 100 mV s for 1000
cycles in 0.5 M H SO4..See DOI: 10.1039/x0xx00000x
2
/CFM. TEM and HAADF-STEM analysis of
The obtained dendritic WSe2 exhibits
a rather low
2
2
/CFM and r-WSe /CFM.
2
overpotential, higher current density at –300 mV vs RHE, and a
small series resistance for HER even at a relatively low coverage of
2
−
1
3
2
2
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WSe and low atom fraction of W and Se (Figure S1). The excellent
Journal Name
2
HER performance is correlated to the high dense edge sites and the
high conductivity of substrates.
The facile CVD approach for WSe
2
with different hierarchical
structures on CFM is exhibited as below, in which (NH ) H W O
4 6 2 12 40
and PAN were selected as the precursors for W and CFM,
respectively (see Supporting Information). Firstly, W-PAN FM was
prepared by electrospinning their DMF solution. Then W-PAN FM
on boat was transferred to the chamber of quartz furnace tube.
Secondly, a heat treatment was employed to pre-oxide PAN FM and
4 6 2 12 3
decompose (NH ) H W O40 into WO . Se vapor was then
introduced at saturated vapor pressure with Ar. Another heat
treatment was applied leading to graphitization of PAN FM and
generation of WSe by selenization of WO and the CFM with WSe
2
3
2
grown on was finally obtained (Figure S2 A). The boat’s lateral
distance from the upstream was adjusted in order to adjust the
vapor concentration. The synthetic route is illustrated in Figure 1A.
More detailed information about preparation can be found in SI.
The obtained CFM with a thickness of 15 μm (Figure S2 B) exhibit
good flexibility and excellent conductivity, and were used as
electrodes directly. The WO3 content within fiber decreases
Figure 1. Schematic illustration of WSe
2
growth at different position
in a quartz furnace tube. SEM images of d-WSe
WSe /CFM and r-WSe /CFM at B, C and D low-, as well as E, F, and
G high-magnification at positions (a), (b) and (c) in (A), respectively.
2
/CFM, TS-
2
2
significantly after selenization as compared to that within WO /CFM
3
(
Figure S2, C and D).
Since the vapor concentration of Se can be diffusion-controlled electron diffraction (SAED), high-angle annular dark field (HAADF)
by the lateral distance from upstream, its influence on the STEM, EELS spectra, element mapping and XPS spectra. As shown in
generated structure of WSe on CFM is illustrated in Figure 1. A Figure 2A, d-WSe branches with 10-80 nm in diameter grew freely
number of flower-like WSe2 in the size of about 2~5 μm was and artistically (Figure 2A). The effective density of edge sites on d-
2
The d-WSe /CFM was fully characterized by TEM, selected area
2
2
obtained at three positions (Figure 1A, (a), (b) and (c)). It’s WSe
interesting to find that three types of microstructures were WSe
2
2
/CFM is believed to be much higher in comparison to that of r-
/CFM. The light and shade contrast indicates the change in the
obtained. Position (a) generated a novel dendritic WSe on CFM thickness (layer number) of WSe
2
branches. The lattice distance
2
(
Figure 1B and 1E), which is defined as d-WSe /CFM. As shown in observed on the terraces is 3.8 Å (left inset in Figure 2A), consistent
2
3
2
Figure 1D and 1G, position (c) can grow smooth leaves of WSe on with (100) planes of 2H-WSe . The SAED (right inset in Figure 2A)
2
2
3
2
CFM with a vivid rose-like shape, which is defined as r-WSe /CFM. clearly suggests that dendritic WSe is configured in 2H phase, in
2
2
The leaves with bended triangular or hexangular contour can be good accordance with the observed triangular or hexangular
distinguished for both d-WSe (Figure 1 E, and Figure S3 A) and r- morphology in Figure 1. As shown in EELS (Figure 2C) and high-
2
WSe2 (Figure 1 G and Figure S3 C). The structure generated at resolution element mapping (Figure 2D), both W and Se elements
position of (b) exhibited a transition morphology (Figure 1C, F and are homogenously distributed within branches. X-ray photoelectron
Figure S3B). The sample at position (b) is defined as TS-WSe /CFM. spectroscopy (XPS) was conducted to investigate the chemical
2
The structure evolution of WSe2 is suggested to be Se vapor composition of d-WSe . Two obvious peaks at 34.2 and 32.1 eV
2
33
concentration sensitive and could be well diffusion-controlled at (Figure 2E) are ascribed to W 4f5/2 and W 4f7/2, respectively. In
different lateral distance from upstream. When the location is close Figure 2F, Se 3d5/2 and Se 3d3/2 at 54.2 and 55.0 eV indicate divalent
to the upstream, the vapor concentration is believed to be high Se ion in good agreement with binding energy values for WSe
2
3
3
supersaturation while a much lower concentration can be achieved crystals. Additonal two weak peaks at around 37.5 and 35.7 eV,
at a faraway distance. The adjusted vapor concentrations at correspondingly assigned to W 4f5/2 and W 4f7/2, are due to a
3
3
different locations thus lead to various structures, which is fraction of WO
(Figure S3D). The TS-WSe
/CFM was also
2
3
3
1
consistent with previous report.
characterized, as shown in Figure S3 E and F.
2
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−1
between 0–1.2 V vs. RHE at 100 mV s for 100 cycles at 25 °C under
Ar bubbling. Both d-WSe /CFM and r-WSe /CFM show onset HER
activity near –150 mV vs. RHE, while CFM, WO /CFM and CVD
synthesized WSe NPs show negligible HER activity. A current
density of 31.7 mA cm is achieved at –300 mV vs RHE for d-
WSe /CFM, which is the highest value for WSe catalyst to the best
of our knowledge as shown in Table S1.
in cathodic current density can also be observed for d-WSe
compared to that of r-WSe /CFM (Figure 3A), indicating that the
dendritic structure is more active since its highly dense edge sites is
beneficial for the hydrogen evolution. However, r-WSe is also a
novel structure for WSe and may be found application for other
2
2
3
2
–2
2
2
1
2, 21, 36, 37
An enhancement
/CFM as
2
2
2
2
research fields. Tafel slope is associated with the elementary steps
in HER. The first step of HER is a discharge step (Volmer reaction) in
which protons are adsorbed to active sites on the surface of the
catalysts and combined with electrons to form adsorbed hydrogen
21
atoms. It is followed by a combination step (Tafel reaction) or a
desorption step (Heyrovsky reaction). From the Tafel slope
calculated (Figure 3B), we estimated the rate determining steps of
−1
−1
our catalyst. As shown in Table S1, 80 mV dec and 163 mV dec
were obtained for d-WSe /CFM and r-WSe /CFM , respectively. The
2
2
−
1
high Tafel slope (163 mV dec ) of r-WSe /CFM, similar to the
2
−1
chemical exfoliated WSe (120 mV dec , ref. 36), indicates that the
2
rate-determining step is the discharge step, with a very small
surface coverage of adsorbed hydrogen. The significant decrease in
2
Figure 2. A) TEM image of dendritic WSe (left inset, HRTEM image;
−1
Tafel slope can be observed for d-WSe /CFM (80 mV dec ), which is
right inset, the corresponding SAED pattern). B) HAADF STEM
images of d-WSe . C) The EELS spectra and D) high-resolution
element mapping of the selected region in Figure B. E) and F) XPS
analysis of W 4f and S 2p peaks of d-WSe /CFM, respectively.
2
attributed to the unique dendritic structure of WSe that reduces
2
2
12
free energy barrier of the discharge step. The electrochemical
double layer capacitance (EDLC) was employed to estimate the
2
3
8
active surface areas of the 3D electrodes, as shown in Figure S8.
The XRD was also employed to evaluate the crystal structure of
d-WSe and r-WSe . As shown in Figure S4, the diffraction peaks are
in consistent with the standard pattern of hexagonal WSe (JCPDS
The EDLC of d-WSe /CFM is about 2.6 times larger than that of r-
2
2
2
WSe /CFM, indicating a highly effective surface area of d-WSe . EIS
2
2
2
was also conducted to study the electrode kinetics at –0.25 V vs
RHE. The EIS results could well exhibit the advantage of the d-
card No. 38-1388). The thickness obtained from the full width at
half-maximum of (002) according to Scherrer equation is 1.2 nm,
WSe /CFM quantitatively. As shown in Figure 3C, nyquist plots
2
3
4
indicating 2 layers of Se-W-Se. The XRD result indicates the same
the crystal structure d-WSe and r-WSe . Raman spectroscopy was
also exploited to further obtain structural evidence of the catalysts
reveals a significant decrease in charge-transfer resistance (RCT) for
d-WSe /CFM (~0.2 Ω) as compared to that of r-WSe /CFM (~1.2 Ω),
2
2
2
2
WO /CFM (~610 Ω) and CFM (~260 Ω). The small resistances show
3
1
(
Figure S5). As both E 2g and A1g modes are very closed to each
the advantage of the facile approach for active electrocatalyst on
conductive substrate, which enables simple and effective electrical
–1 21
2
other, at 250 and 253 cm , accordingly, only one peak for WSe is
observed. The above Raman result for the two hierarchical
structures further substantiates the same crystal structure. Two
39
integration that minimize Ohmic losses. The HER catalytic
activities of d-WSe /CFM, and r-WSe /CFM are believed associated
2
2
–1
–1
broad peaks at 1354.5 cm and 1587.6 cm correspond to the D
and G band of the CFM. The intensity ratio of D and G bands (I /I
is 1.15. The presence of graphitic is expected to achieve a high
with their diffierent morphologies and electronic properties, which
39
D
G
)
play very important roles in the overall HER performance. The as-
2
synthesized 3D dendritic WSe electrode with a small Tafel slope,
35
conductive CFM substrate.
The d-WSe /CFM was directly used as hydrogen evolution
cathode to highlight the merits of the novel architecture. The
configuration of d-WSe /CFM electrode is shown in Figure S6. CFM,
WO /CFM, WSe NPs (Figure S7) and r-WSe /CFM electrodes were
large available surface area as well as small resistances is a
promising candidate for HER applications.
2
2
3
2
2
also tested as control. The electrochemical experiment was
conducted in a standard three-electrode electrochemical cell setup
in 0.5 M H
2 4
SO electrolyte. A resistance test was obtained (~8 Ω) via
electrochemical impedance spectroscopy (EIS) and iR compensation
–1
was applied. Figure 3A shows the polarization curves at 5 mV s
with current density normalized by geometric surface area. Initial
cleaning of the electrocatalyst surface was performed by cycling
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Journal Name
Hydrogen ions at the active sites of WSe
2
catalyst are reduced by
the transferred electrons, followed by release of hydrogen gas. For
the d-WSe /CFM, the electrolyte containing hydrogen ions can
2
access large amount of edge sites through the dendritic structure,
leading to much more hydrogen bubbles released from the
2
electrode. r-WSe /CFM exhibits a relatively poorer performance
2
due to the less edge sites on the smooth leaves of WSe .
Conclusions
In summary, dendritic WSe
and synthesized by a diffusion-controlled CVD method. The d-
WSe /CFM exhibits remarkable enhancement in HER performance
due to the effectively exposed edge sites. Moreover, the much
lower charge-transfer resistance of d-WSe /CFM, the high
2
on conductive CFM was designed
2
2
conductivity of carbon nanofiber and the formed 3D structure are
experimentally verified and well correlated to the improvement of
Figure 3. A) Polarization curves (after iR correction) obtained with HER activity. Above all, a facile method for synthesizing 3D
several catalysts as indicated. B) Corresponding Tafel plots for r- structural electrode was established. It will open up a new pathway
WSe /CFM, d-WSe /CFM and Pt/C. C) EIS Nyquist plots collected at for developing more efficient HER catalysts in the near future.
2
2
a bias voltage of –0.250 V vs RHE. D) Time dependence of current
density under static overpotential of –0.215 V vs RHE. Inset is the
enlargement of the area denoted by the dash circle.
Acknowledgements
This work was supported by the National Natural Science
Foundation of China (NSFC) (Grant No. 51373154 and 21203137)
and the 521 Talent Project of Zhejiang Sci-Tech University.
Furthermore, two types of durability tests of d-WSe /CFM
2
were also conducted. The CV test for 1000 cycles (Figure S9)
indicated that excellent stability of the electrode. The SEM and TEM
images of d-WSe /CFM after 1000 cycles were also obtained (Figure
2
S10). In fact, the morphology and structure of d-WSe /CFM do not
2
Notes
get obvious change after 1000 CV cycles, futher indicating the good
stability of the catalyst. The other durability test, time dependence
of current density at a constant potential for a period of time
1
These authors contributed equally.
Corresponding author
*
(
Figure 3D) implied that the current density reach a constant after
References
an acceptable slight decrease. Although a serrate shape of current
was observed that is relative to the alternate processes of bubble
accumulation and the bubble release.
1
2
3
4
5
6
7
8
I. Dincer, C. Acar, Int. J. Hydrogen Energy, DOI:
http://dx.doi.org/10.1016/j.ijhydene.2014.12.035.
Y. Zheng, Y. Jiao, M. Jaroniec and S. Z. Qiao, Angew. Chem.
Int. Edit., 2015, 54, 52-65.
Y. H. Chang, C. T. Lin, T. Y. Chen, C. L. Hsu, Y. H. Lee, W.
Zhang, K. H. Wei and L. J. Li, Adv. Mater., 2013, 25, 756-760.
D. V. Esposito, S. T. Hunt, Y. C. Kimmel and J. G. Chen, J. Am.
Chem. Soc., 2012, 134, 3025-3033.
W. F. Chen, J. T. Muckerman and E. Fujita, Chem. Comm.,
2
013, 49, 8896-8909.
H. H. Li, C. H. Cui, S. Zhao, H. B. Yao, M. R. Gao, F. J. Fan and
S. H. Yu, Adv. Energy Mater., 2012, , 1182-1187.
X. Cao, Y. Han, C. Gao, Y. Xu, X. Huang, M. Willander and N.
Wang, Nano Energy, 2014, , 301-308.
2
9
C. Wang, M. Chi, G. Wang, D. van der Vliet, D. Li, K. More, H.
H. Wang, J. A. Schlueter, N. M. Markovic and V. R.
Stamenkovic, Adv. Funct. Mater., 2011, 21, 147-152.
9
1
S. Shin, Z. Jin, D. H. Kwon, R. Bose and Y. S. Min, Langmuir,
Figure 4. Schematic illustration of electrochemical behavior of d-
2
014, 31, 1196-1202.
0 H. Tang, K. Dou, C. C. Kaun, Q. Kuang and S. Yang, J. Mater.
Chem. A, 2014, , 360-364.
WSe /CFM and r-WSe /CFM for HER.
2
2
The electrochemical behaviors of d-WSe /CFM and r-
2
2
WSe /CFM are illustrated in Figure 4. Electrons can transfer through
2
the carbon nanofiber to WSe2 catalyst that grown on the CFM.
4
| J. Mater. Chem. A, 2015, 00, 1-3
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Please do not adjust margins

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1
1 M. A. Lukowski, A. S. Daniel, C. R. English, F. Meng, A. 37 J. M. Velazquez, F. H. Saadi, A. P. Pieterick, J. M. Spurgeon,
Forticaux, R. J. Hamers and S. Jin, Energ. Environ. Sci., 2014,
, 2608-2613.
M. P. Soriaga, B. S. Brunschwig and N. S. Lewis, J. Electroanal.
Chem., 2014, 716, 45-48.
7
1
1
1
2 K. Xu, F. Wang, Z. Wang, X. Zhan, Q. Wang, Z. Cheng, M. 38 D. S. Kong, H. T. Wang, Z. Y. Lu, Y. Cui, J. Am. Chem. Soc.
Safdar and J. He, ACS Nano, 2014, 8, 8468-8476. 2014, 136, 4897-4900
3 C.Tsai, K. Chan, F. Abild-Pedersen and J. K. Nørskov, Phys. 39 M. A. Lukowski, A. S. Daniel, F. Meng, A. Forticaux, L. Li, S.
Jin, J. Am. Chem. Soc., 2013, 135, 10274-10277.
Chem. Chem. Phys., 2014, 16, 13156-13164.
4 D. Y. Chung, S. K. Park, Y. H. Chung, S. H. Yu, D. H. Lim, N.
Jung, H. C. Ham, H. Y. Park, Y. Piao, S. J. Yoo and Y. E. Sung,
Nanoscale, 2014, 6, 2131-2136.
1
1
5 X. L. Zheng, J. B. Xu, K. Y. Yan, H. Wang, Z. L. Wang and S. H.
Yang, Chem. Mater. 2014, 26, 2344-2353.
6 D. Y. Chung, S. Park, Y. Chung, S. Yu, D. Lim, N. Jung, H. C.
Ham, H. Park, Y. Piao, S. J. Yoo and Y. Sung, Nanoscale, 2014,
6
, 2131-2136.
7 B. Liu, T. Luo, G. Mu, X. Wang, D. Chen and G. Shen, ACS
Nano, 2013, , 8051-8058.
1
1
1
7
8 H. Fang, S. Chuang, T. C. Chang, K. Takei, T. Takahashi and A.
Javey, Nano Lett., 2012, 12, 3788-3792.
9 R. Cheng, D. Li, H. Zhou, C. Wang, A. Yin, S. Jiang, Y. Liu, Y.
Chen, Y. Huang and X. Duan, Nano Lett., 2014, 14, 5590-
5
597.
0 W. Zhang, M. H. Chiu, C. H. Chen, W. Chen, L. J. Li and A. T. S.
Wee, ACS Nano, 2014, , 8653-8661.
2
2
2
8
1 H. Wang, D. Kong, P. Johanes, J. J. Cha, G. Zheng, K. Yan, N.
Liu and Y. Cui, Nano Lett., 2013, 13, 3426-3433.
2 H. Zhu, M. L. Du, M. Zhang, M. L. Zou, T. T. Yang, S. L. Wang,
J. M. Yao and B. C. Guo, Chem. Commun., 2014, 50, 15435-
1
5438.
3 H. Zhu, M. L. Du, M. Zhang, M. L. Zou, T. T. Yang, Y. Q. Fu and
J. M. Yao, J. Mater. Chem. A, 2014, , 7680-7685.
4 H. Zhu, F. L. Lyu, M. L. Du, M. Zhang, Q. F. Wang, J. M. Yao
2
2
2
and B. C. Guo, ACS Appl. Mater. Inter., 2014,
5 I. Sunagawa, Forma, 1999, 14, 147-166.
6, 22126-22137.
2
2
6 S. Jin, M. J. Bierman and S. A. Morin, J. Phys. Chem. Lett.,
010, , 1472-1480.
7 G. Zhang, S. Sun, M. Cai, Y. Zhang, R. Li and X. Sun, Sci. Rep.,
013, , 1526.
8 L. Chen, B. Liu, A. N. Abbas, Y. Ma, X. Fang, Y. Liu and C. Zhou,
ACS Nano, 2014, , 11543-11551.
2
1
2
2
2
3
3
3
2
3
8
9 A. Zhuang, J. J. Li, Y. C. Wang, X. Wen, Y. Lin, B. Xiang, X.
Wang and J. Zeng, Angew. Chem., 2014, 126, 6543-6547.
0 C. Li, L. Huang, G. P. Snigdha, Y. Yu and L. Cao, ACS Nano,
2
012, 6, 8868-8877.
1 S. Wang, Y. Rong, Y. Fan, M. Pacios, H. Bhaskaran, K. He and
J. H. Warner, Chem. Mater., 2014, 26, 6371-6379.
2 J. K. Huang, J. Pu, C. L. Hsu, M. H. Chiu, Z. Y. Juang, Y. H.
Chang, W. H. Chang, Y. Iwasa, T. Takenobu and L. J. Li, ACS
Nano, 2013, 8, 923-930.
3
3
3
3
3 H. Wang, D. Kong, P. Johanes, J. J. Cha, G. Zheng, K. Yan, N.
Liu and Y. Cui, Nano Lett., 2013, 13, 3426-3433.
4 J. Xie, H. Zhang, S. Li, R. Wang, X. Sun, M. Zhou, J. Zhou, X. W.
Lou and Y. Xie, Adv. Mater., 2013, 25, 5807-5813.
5 S. Chen, J. Duan, Y. Tang, B. Jin and S. Zhang Qiao, Nano
Energy, 2015, 11, 11-18.
6 A. Y. S. Eng, A. Ambrosi, Z. Sofer, P. Šimek and M. Pumera,
ACS Nano, 2014, 8, 12185-12198.
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DOI: 10.1039/C5TA02538A
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D dendritic WSe on conductive carbon nanofiber mats (d-WSe2/CFM) was
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synthesized and directly used as hydrogen evolution cathode.