Tannic acid decorated AuPd lavender-like nanochains for enhanced oxygen reduction electrocatalysis

Article abstract of DOI:10.1039/d1ta04114b

Benefiting from the interaction of inorganic and organic building blocks, the design of metal-organic nanohybrids is of great significance for the oxygen reduction reaction (ORR). Herein, a universal strategy is presented to controllably synthesize tannic acid (TA) functionalized AuPd lavender-like nanochains (AuPd@TA LCs) by a chemical reduction method at low temperature. Due to the unique structural characteristics and polyphenolic modification, the AuPd@TA LCs show superior ORR performance in an alkaline electrolyte. Moreover, the surface decorated TA polymers can act as a molecular screen window to prevent methanol molecules from accessing the active site of the catalyst, thus resulting in high methanol tolerance and catalytic stability. The presented molecular screen window strategy is highly valuable for designing ORR electrocatalysts with high methanol tolerance.

Full text of DOI:10.1039/d1ta04114b

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Materials Chemistry A
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Tannic acid decorated AuPd lavender-like
nanochains for enhanced oxygen reduction
electrocatalysis†
Cite this: J. Mater. Chem. A, 2021, 9,
15678
Shuli Yin, Songliang Liu, Shiqian Jiao, Hugang Zhang, You Xu,
Ziqiang Wang,
*
Xiaonian Li, Liang Wang
and Hongjing Wang
Benefiting from the interaction of inorganic and organic building blocks, the design of metal–organic
nanohybrids is of great significance for the oxygen reduction reaction (ORR). Herein, a universal strategy
is presented to controllably synthesize tannic acid (TA) functionalized AuPd lavender-like nanochains
(AuPd@TA LCs) by a chemical reduction method at low temperature. Due to the unique structural
characteristics and polyphenolic modification, the AuPd@TA LCs show superior ORR performance in an
alkaline electrolyte. Moreover, the surface decorated TA polymers can act as a molecular screen window
to prevent methanol molecules from accessing the active site of the catalyst, thus resulting in high
methanol tolerance and catalytic stability. The presented molecular screen window strategy is highly
valuable for designing ORR electrocatalysts with high methanol tolerance.
Received 15th May 2021
Accepted 19th June 2021
DOI: 10.1039/d1ta04114b
rsc.li/materials-a
the crystal structure, morphology, size, surface structure and
elemental composition of the electrocatalysts.29–34 Therefore,
Introduction
the invention of a kind of nanomaterial with controllable
structure and morphology with good repeatability and high
yield is of great signicance to obtain promising Pd-based
catalysts.35–39 Among the various morphologies of catalysts, 1D
nanomaterials, with the advantages of high mass transport, fast
electron communication and anti-agglomeration, possess effi-
cient electrocatalytic activity and stability for the ORR and MOR,
which could be attributed to the surface index control and high
aspect ratio.40–42 Thereinto, Au nanowires (Au NWs) with high
conductivity are conducive to improving the reaction kinetics of
the catalyst. Besides, AuPd bimetallic materials have been re-
ported to have superior catalytic activity due to the electronic
and synergistic effect between Au and Pd. Therefore, it is highly
desirable to nd a strategy for the synthesis of 1D AuPd nano-
catalysts with a large amount of accessible area to improve the
ORR performance.
Numerous studies have shown that surface modication
can signicantly improve the electrocatalytic performance of
materials.43–46 In addition, metal–organic nanohybrids,
combining the double characteristics of inorganic and
organic materials, have attracted much attention.47–49 There-
fore, it is worth exploring whether the electrocatalytic activity
can be improved by modifying a layer of organic matter on the
surface of noble metals. Chen and co-workers have conrmed
that polyethylenimine functionalized Au nanowires@Pd core–
shell bimetallic nanohybrids exhibit excellent electrocatalytic
activity toward the ORR.50 Inoue and co-workers have reported
that surface decoration of the Pt/Pd/C catalysts with mela-
mine or polymerized melamine can signicantly enhance the
Direct methanol fuel cells (DMFCs), which can convert chemical
energy into electrical energy, have been intensively developed.1–5
As the cathodic reaction of DMFCs, the oxygen reduction reac-
tion (ORR) has attracted much attention.6–9 Pt electrocatalyst
has been widely used in the ORR, but further development of
the catalyst is limited by its shortcomings such as poor storage,
slow kinetics and easy poisoning.10–15 Pd, which has a very
similar electronic structure to that of Pt, can be used as a good
substitute for Pt, showing superior ORR performance in alka-
line fuel cells.16–20 Since there are many similarities between Pd
and Pt, Pd-based materials are bound to be good electro-
catalysts for the methanol oxidation reaction (MOR) in alkaline
electrolytes.21–23 In DMFCs, the intermediate product CO
generated by the MOR of the anode inevitably cross-interferes
with the cathode, thus poisoning the cathodic Pd-based cata-
lysts.24,25 Therefore, synthesis of catalysts with excellent ORR
performance and superior methanol tolerance by ingenious
design would be a breakthrough in the architecture of Pd-based
materials.
Although there have been many studies on Pd-based mate-
rials, the ORR electrocatalytic mechanism in alkaline electro-
lytes still has blind spots.26–28 The origin of this difficulty is
mainly the determinants of the ORR performance, including
State Key Laboratory Breeding Base of Green-Chemical Synthesis Technology, College
of Chemical Engineering, Zhejiang University of Technology, Hangzhou 310014, P. R.
China. E-mail: hjw@zjut.edu.cn
† Electronic supplementary information (ESI) available. See DOI:
10.1039/d1ta04114b
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ORR activity.51 Such evidence suggests that specic organic
modication can effectively improve the performance of the
ORR. Tannic acid (TA) is a natural polyphenol widely found in
many plants with good water solubility and environmental
friendliness.52–54 TA contains a large number of phenolic
hydroxyl groups, and can form metal–phenolic nanohybrids
with metals.55 Similar to polyethylenimine and polymerized
melamine, whether the modication by TA can enhance the
ORR activity of Pd-based nanomaterials has become a new hot
topic. Another advantage of the organic modication of
a metal surface is that a layer of molecular screen window can
be formed on the surface of the catalyst to prevent the contact
between methanol and the active site, thus reducing CO
toxicity and making the catalyst more stable.50
Herein, a strategy to fabricate TA decorated AuPd lavender-
like nanochains (AuPd@TA LCs), a metal–organic nanohybrid,
by surface modication of the pre-synthesized AuPd lavender-
like nanochains (AuPd LCs) with TA is presented. The
AuPd@TA LCs exhibit superior ORR performance with high
methanol tolerance.
Results and discussion
The model shown in Fig. 1 describes the process of modifying
AuPd LCs prepared in advance with TA to obtain AuPd@TA LCs.
Beneting from the electrochemical self-stability of the Au-
based material and the superiority of the 1D material, Au
NWs are selected as the starting core. Scanning electron
microscopy (SEM) and transmission electron microscopy (TEM)
images show that ultra-long Au NWs with a uniform diameter
(5.3 nm) have been synthesized (Fig. S1†). The synthesis of
anisotropic Au NWs is induced by multifunctional 1-naphthol.56
The high surface area of Au NWs is benecial to the growth of
Pd nanoparticles on the outside, resulting in a lavender-like
nanochain structure of AuPd LCs. Then, the synthesized
initial material is mixed with TA at room temperature and
stirred for 3 h to obtain organic functionalized AuPd@TA LCs
with controllable morphology.
The morphology and structure of the catalysts before and
aer surface modication were analyzed by SEM and TEM. As
can be seen from the SEM image, AuPd LCs maintain the super-
long structure of the Au NWs, but have a bumpy surface (Fig.-
S2a†). A subtler structure is represented in the TEM image
which shows that AuPd LCs have a lavender-like nanochain
structure composed of ultra-long nanowires inside and nano-
particles growing on the surface (Fig. S2b†). AuPd@TA LCs were
obtained aer surface modication of AuPd LCs with TA.
Similar to that of AuPd LCs, the SEM image of AuPd@TA LCs
still exhibits a nanowire-like structure with unsmooth surfaces
(Fig. 2a). TEM characterizations are used to further analyze the
structure and surface modication of AuPd@TA LCs. The TEM
image at low magnication demonstrates the unique structure
of nanoparticles anchored on nanowires (Fig. 2b). The nano-
particles are evenly distributed on the surface of the high-
quality nanowires, indicating an extremely high yield of
AuPd@TA LCs. The high magnication TEM image can clearly
distinguish a layer of amorphous substance attached to the
material surface which is presumed to be the successful
modication of AuPd LCs by TA (Fig. 2c). The edge structure of
AuPd@TA LCs is analyzed from the high-resolution TEM
(HRTEM) image, and a layer of amorphous substance of about
2.1 nm is observed (Fig. 2d). In addition, clear lattice lines with
a spacing of 0.23 nm are found in the sub-outer layer, which
corresponded exactly to the (111) plane of the Pd face-centered
cubic (fcc) structure. High-angle annular dark-eld scanning
TEM (HAADF-STEM) distinctly reveals the lavender-like nano-
chain structure of AuPd@TA LCs (Fig. 2e). The elemental
Experimental
Reagents and chemicals
HAuCl4$3H2O, 1-naphthol, L-ascorbic acid (AA), Naon 117,
tetrahydrofuran (THF), Na2PdCl4, TA, HCl, KOH and HClO4
were supplied by Aladdin Industrial Corporation. Poly(styrene)-
b-poly(ethylene oxide) (PS3800-b-PEO5000) was purchased from
Polymer Source, Inc. Pd black and commercial Pt/C (20 wt% Pt)
were purchased from Alfa Aesar.
Synthesis of AuPd@TA LCs
Typically, Na2PdCl4 (0.25 mL, 80 mM) solution was mixed with
THF (0.12 mL) containing 4 mg of PS-b-PEO. Then, H2O (0.55
mL), Au NWs (0.05 mL) and HCl (80 mL, 2 M) were injected.
Finally, 1 mL of AA (0.1 M) solution was introduced to trigger
the reduction in a 50 ꢀC water bath and the reaction was allowed
to proceed for 10 h. AuPd LCs were obtained by centrifugation
and washing. The AuPd@TA LCs were synthesized just by
dispersing AuPd LCs in 15 mL TA (0.051 g) solution and stirring
at room temperature for 3 h. The detailed synthetic process of
Au NWs is provided in the ESI.†
Electrochemical measurements
The ORR electrochemical tests were accomplished with a CHI
852D workstation equipped with an ALS RRDE-3A rotating
ring disk electrode meter. The measurements were carried out
in a three-electrode system in O2-saturated 0.1 M KOH. A
rotating disk electrode, Ag/AgCl electrode and a Pt wire were
used as the working electrode, reference electrode and
counter electrode, respectively. The catalyst loading on the
working electrode was controlled at 2 mg of metal. Then, 2 mL
of Naon (0.5%) was coated on the surface of the catalyst to
prevent it from falling off.
Fig. 1 Schematic illustration of the synthesis of AuPd@TA LCs.
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indicates that Na2PdCl4 is reduced to metallic Pd during the
synthesis of AuPd LCs. Fig. 3 shows the XPS spectra of
AuPd@TA LCs. The XPS peak position of Au 4f is similar to that
of AuPd LCs, indicating that surface modication has no effect
on the internal Au NWs (Fig. 3a). In the XPS spectrum of the Pd
3d orbit, the two strong peaks with binding energies located at
341.05 and 335.77 eV correspond to the 3d3/2 and 3d5/2 orbitals
of Pd(0), respectively (Fig. 3b), which are similar to those for
AuPd LCs, revealing no effect of TA modication on the elec-
tronic structure of Pd. In the XPS spectrum of the C 1s orbit, the
three strong peaks with binding energies located at 288.44,
285.95 and 284.10 eV correspond to O]C–O, C–O and C–H
species, respectively (Fig. 3c). In the XPS spectrum of the O 1s
orbit, the three strong peaks with binding energies located at
533.03, 532.14 and 531.36 eV correspond to C–O, O–H and C]O
species, respectively (Fig. 3d).57 The XPS spectra of AuPd LCs
and AuPd@TA LCs demonstrate that the lavender-like nano-
chain structure has been formed and the TA modication has
not adversely altered the structure. Fig. S6† shows the Fourier
transform infrared (FT-IR) spectra of AuPd@TA LCs and TA.
Consistent with TA, the FT-IR spectrum of AuPd@TA LCs has
ve distinct characteristic peaks, including conjugated C]O
stretching vibration (located at 1719 cmÀ1), aromatic C]C
stretching vibration (located at 1451 cmÀ1), C–O stretching
(located at 1337 and 1200 cmÀ1), and C–H out-of-plane bending
(located at 756 cmÀ1),57 indicating that TA has been successfully
modied on the surface of AuPd@TA LCs. The results of the
physical phase characterizations illustrate that we have
successfully prepared such a TA-modied lavender-like nano-
chain structure with Au NWs as the core and Pd nanoparticles
as the humps. The organic surface modication and control-
lable physicochemical structural characteristics of AuPd@TA
Fig. 2 (a) SEM image and (b and c) TEM images of the AuPd@TA LCs.
(d) HRTEM image of the AuPd@TA LCs and Fourier filtered lattice fringe
image of the selected area. (e) HAADF-STEM image of a AuPd@TA LC,
and (f) corresponding elemental mapping images.
mapping analysis of this material reveals that Au, Pd, C and O
elements are distributed on AuPd@TA LCs (Fig. 2f). Among
them, Au element is distributed in the core part of the chain-like
structure, which proves that the Au NWs can be used as the
starting core to induce epitaxial growth. Pd element is mainly
distributed in the sub-outer layer of AuPd@TA LCs, just corre-
sponding to the bulge of the chain-like structure, indicating
that Pd species grow on Au NWs and form the nanoparticles.
The C and O elements are distributed in the outermost layer,
indicating that TA has been successfully modied on the
surface of the catalyst. SEM and TEM characterization results
indicate that TA-modied lavender-like nanostructures with Au
NWs as the core have been successfully prepared.
The crystal structure and elemental composition of AuPd
LCs and AuPd@TA LCs were revealed by X-ray diffraction (XRD)
and X-ray photoelectron spectroscopy (XPS) characterization
data. The existing peaks corresponding to the standard fcc Au
(JCPDS-04-0884) and fcc Pd (JCPDS-46-1043) can be distin-
guished from the XRD pattern of AuPd LCs, indicating that the
pure Pd nanoparticles grow on the pure Au NWs (Fig. S3a†).
Compared with that of AuPd LCs, the XRD pattern of AuPd@TA
LCs does not change much, but the relative diffraction intensity
of Pd is weakened (Fig. S3b†). This phenomenon may be caused
by the outer coating of TA, and the modication of TA has no
effect on the crystal structure of AuPd LCs. The elemental
compositions and valence states of AuPd LCs and AuPd@TA
LCs are studied from XPS spectrograms. Obvious peaks (Pd 3d
orbital and Au 4f orbital) and weak peaks (C 1s orbital and O 1s
orbital) exist in the XPS spectrum of AuPd LCs (Fig. S4a†). In
contrast, in the XPS spectrum of AuPd@TA LCs, in addition to
the obvious peaks of the Pd 3d orbital and Au 4f orbital, the
intensity of the peaks of the C 1s orbital and O 1s orbital has
been greatly improved, indicating that TA has been successfully
modied on the material surface (Fig. S4b†). Specically, there
are two distinct diffraction peaks located at 87.33 and 83.65 eV
in the XPS spectrum of Au 4f for AuPd LCs, corresponding to the
4f5/2 and 4f7/2 orbits of Au(0). It indicates that the fully metallic
state of Au is present in AuPd LCs (Fig. S5a†). In the XPS spec-
trum of Pd 3d, a group of strong peaks corresponding to the 3d3/
LCs are highly favorable for
performance.
a superior electrochemical
Inspired by the surface modication combined with the
lavender-like nanochain structure, the electrochemical proper-
ties of AuPd@TA LCs toward the ORR under alkaline conditions
Fig. 3 XPS spectra of (a) Au 4f, (b) Pd 3d, (c) C 1s and (d) O 1s for the
AuPd@TA LCs.
and 3d5/2 orbitals of Pd(0) can be detected (Fig. S5b†).This
2
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were investigated. AuPd LCs, Pt/C and Pd black catalysts were of hydrogen desorption which is 51.1 m2 gÀ1. The specic
used as references to explore the impacts of TA surface modi- activity (SA, normalized to ECSA) of AuPd@TA LCs is 1.87 mA
cation and structure controllability. The ORR activity of cmÀ2 which is higher than that of AuPd LCs (0.56 mA cmÀ2) and
AuPd@TA LCs is reected by linear sweep voltammograms is 5.84 times as much as that of Pt/C. The mass activity (MA,
(LSVs) measured in O2-saturated 0.1 M KOH solution at a scan normalized to the mass of metal) of AuPd@TA LCs is 0.90 A
rate of 5 mV sÀ1 with a rotation rate of 1600 rpm (Fig. 4a). To mgmetal
which is higher than that of AuPd LCs (0.37 A
À1
explore the inuence of surface modication and structure mgmetalÀ1) and is 5.62 times as much as that of Pt/C (Fig. 4d).
controllability on the catalytic activity, LSV curves of AuPd LCs, Compared with many Pd-based ORR catalysts that have been
Pt/C and Pd black catalysts are obtained simultaneously. reported, AuPd@TA LCs have higher SA or MA (Table S1†). The
Compared with AuPd LCs, AuPd@TA LCs have a more positive dynamics of the ORR process also can be conrmed from LSV
reduction potential and a larger limiting current density (5.49 curves at various rotation rates. As shown in Fig. S8a,† the
mA cmÀ2), indicating that the modication of TA can effectively current density of AuPd@TA LCs presents regular changes at
improve the activity towards the ORR. In addition, the novel different rotation rates. Four different lines are obtained by
lavender-like nanochain structure results in a more positive tting the current density at four continuous potentials
reduction potential and a larger limiting current density of according to the Koutecky–Levich (K–L) equation (Fig. S8b†).
AuPd@TA LCs than that of Pt/C (5.13 mA cmÀ2) and Pd black Calculations show that the electron transfer numbers (n) of
(3.57 mA cmÀ2). The dynamics of the ORR process are AuPd@TA LCs at each potential are close to 4. Calculations
conrmed by the Tafel plots near the reduction potential. As using the K–L equation reveal that n for both AuPd LCs
Fig. 4b shows, the Tafel slope of AuPd@TA LCs deduced from (Fig. S9†) and Pt/C (Fig. S10†) is close to 4. A one-step four-
the LSV curve is 56 mV decÀ1, signicantly lower than that of electron pathway in the ORR process occurring on AuPd@TA
AuPd LCs (64 mV decÀ1), Pt/C (69 mV decÀ1) and Pd black LCs is conrmed through n.
(131 mV decÀ1). The fact that AuPd@TA LCs have a smaller
The catalytic stabilities of AuPd@TA LCs, AuPd LCs and Pt/C
Tafel slope indicates the enhanced dynamics for the ORR. The toward the ORR are assessed by conducting accelerated dura-
onset potential (Eonset) and half wave potential (E1/2) analyzed bility tests. Aer 5000 cycles of continuous potential cycling, the
from LSV cures are used to evaluate the ORR performance more LSV curve of AuPd@TA LCs (Fig. 5a) shows a negligible change,
intuitively (Fig. 4c). Compared with AuPd LCs (0.99 V, 0.87 V), while the LSV curve of AuPd LCs (Fig. 5b) shows a distinct
Pt/C (0.96 V, 0.85 V) and Pd black (0.94 V, 0.80 V), AuPd@TA LCs change at the limiting current density (0.16 mA cmÀ2) and E1/2
show higher Eonset (1.01 V) and E1/2 (0.90 V). Fig. S7† shows the (5 mV). Pt/C also shows a slight decay in E1/2 and limiting
cyclic voltammogram (CV) curves recorded in N2-saturated current aer 5000 cycles (Fig. 5c). Chronoamperometric
0.1 M HClO4 solution at a scan rate of 50 mV sÀ1 which can be measurements are carried out at 0.4 V to evaluate the long-term
used to estimate the electrochemically active surface areas stability of the three catalysts. Aer testing for 5 h, the current of
(ECSAs) of different samples. The ECSAs of AuPd@TA LCs and AuPd@TA LCs only decays by 8.38%, while AuPd LCs and Pt/C
AuPd LCs are calculated from the reduction peak of Pd which decay by 12.92% and 19.80%, respectively (Fig. 5d). The TEM
are 48.0 and 65.2 m2 gÀ1, respectively. The ECSA of AuPd@TA image of AuPd@TA LCs aer long-term stability testing shows
LCs is slightly lower than that of AuPd LCs, which indicates that that the modied TA is stable, indicating that AuPd@TA LCs
the loosely packed TA polymer membrane with high porosity have prominent structural stability (Fig. S11†). In addition, the
covering the surface could block only a very small number of TEM image of AuPd@TA LCs aer the test in 0.1 M HClO4
metal active sites. The ECSA of Pt/C is calculated from the area
Fig. 4 (a) ORR polarization curves, (b) Tafel slopes, (c) Eonset and E1/2 Fig. 5 (a–c) ORR polarization curves for the three catalysts before and
for different catalysts in an O2-saturated 0.1 M KOH solution. (d) SA and after the durability test. (d) Chronoamperometric curves at 0.4 V with
MA at 0.85 V for AuPd@TA LCs, AuPd LCs and Pt/C.
a rotation rate of 1600 rpm.
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to obtain AuPd@TA LCs with a lavender-like nanochain struc-
ture. The AuPd@TA LCs exhibit excellent activity, stability, and
methanol tolerance toward the ORR under alkaline conditions.
Compared with Pt/C and Pd black, Au NWs anchored by Pd
nanoparticles can provide more accessible active sites, thus
effectively improving ORR catalytic performance. In addition,
the outer loosely packed TA layer has a methanol-phobic
property, which prevents the methanol from contacting the
active site to prevent catalyst poisoning. This work provides
a molecular screen window strategy for the enhancement of the
ORR performance by surface modication of TA on metal
electrocatalysts.
Fig. 6 (a) CV curves in 0.1 M KOH with 1 M CH3OH solution. (b) I–t
response in an O2-saturated 0.1 M KOH solution with 3 M CH3OH
added at around 600 s.
solution is obtained, revealing that TA is also stable in acid
media (Fig. S12†). The stability measurement results indicate
that TA modication can greatly improve the stability of the
ORR in alkaline solutions.
Conflicts of interest
The authors declare no competing nancial interest.
CV curves in 0.1 M KOH and 1 M methanol solution are
recorded to investigate the methanol tolerance of the catalysts
(Fig. 6a). In the presence of methanol, AuPd LCs and Pt/C show
obvious methanol oxidation peaks, and the methanol oxidation
performance of AuPd LCs is still favorable. It is worth noting
that the methanol oxidation peak of AuPd@TA LCs is very faint,
indicating that the TA can act as a molecular screen window to
block the contact between methanol and the catalytic active site.
Chronoamperometric investigation measurements are carried
out to further identify the methanol tolerance of the AuPd@TA
LCs. In the long-term stability test, the currents of the three
catalysts decrease to a certain extent when 3 M methanol is
added at 600 s (Fig. 6b). However, the current attenuation
degree of AuPd@TA LCs is far less than that of AuPd LCs and Pt/
C, which proves that AuPd@TA LCs can effectively avoid being
poisoned.
It is evident from the above physical characterizations and
electrochemical measurements that the already synthesized
organic–metal hybrid AuPd@TA LCs with a lavender-like
nanochain structure exhibit excellent activity, stability, and
methanol tolerance for the ORR. The catalytic activity of AuPd
LCs is higher than that of Pt/C and Pd black, conrming that the
unique structure of Pd nanoparticles anchored on the Au NWs
could fully expose the catalytic active sites and effectively
enhance the ORR activity. In addition, compared with AuPd
LCs, AuPd@TA LCs modied by TA have better activity and
stability, indicating that the surface modication of organic
matter can accelerate the adsorption and reaction of oxygen,
meanwhile, they can also prevent the catalyst from sintering
and maintain excellent stability. More notably, AuPd@TA LCs
display superior methanol tolerance when methanol is present
in the electrolyte, because the TA on the surface can act as
a molecular screen window allowing only small molecules to get
through and block the contact between methanol and the
catalytic active site, thus preventing CO poisoning.
Acknowledgements
This work was nancially supported by the National Natural
Science Foundation of China (No. 21601154, 21776255,
21972126, 21978264 and 21905250).
References
1 Y. Zhang, B. Huang, G. Luo, T. Sun, Y. Feng, Y. Wang, Y. Ma,
Q. Shao, Y. Li, Z. Zhou and X. Huang, Sci. Adv., 2020, 6,
eaba9731.
2 Z. Xia, X. Zhang, H. Sun, S. Wang and G. Sun, Nano Energy,
2019, 65, 104048.
3 X. Wang, M. Xie, F. Lyu, Y. M. Yiu, Z. Wang, J. Chen,
L. Y. Chang, Y. Xia, Q. Zhong, M. Chu, H. Yang, T. Cheng,
T. K. Sham and Q. Zhang, Nano Lett., 2020, 20, 7751–7759.
4 Z. Li, S. Xu, Y. Shi, X. Zou, H. Wu and S. Lin, Chem. Eng. J.,
2021, 414, 128814.
´
˜
5 J. C. Abrego-Martınez, A. Moreno-Zuria, F. M. Cuevas-Muniz,
L. G. Arriaga, S. Sun and M. Mohamedi, J. Power Sources,
2017, 371, 10–17.
6 I. Martinaiou, A. H. A. Monteverde Videla, N. Weidler,
¨
M. Kubler, W. D. Z. Wallace, S. Paul, S. Wagner,
A. Shahraei, R. W. Stark, S. Specchia and U. I. Kramm,
Appl. Catal., B, 2020, 262, 118217.
7 V. Jose, J. M. V. Nsanzimana, H. Hu, J. Choi, X. Wang and
J. M. Lee, Adv. Energy Mater., 2021, 11, 2100157.
´
8 G. Zhang, D. Sebastian, X. Zhang, Q. Wei, C. Lo Vecchio,
`
J. Zhang, V. Baglio, W. Wang, S. Sun, A. S. Arico and
A. C. Tavares, Adv. Energy Mater., 2020, 10, 2000075.
9 X.-T. Wang, T. Ouyang, L. Wang, J.-H. Zhong and Z.-Q. Liu,
Angew. Chem., Int. Ed., 2020, 132, 6554–6561.
10 X. Jiang, K. Elouarzaki, Y. Tang, J. Zhou, G. Fu and J.-M. Lee,
Carbon, 2020, 164, 369–377.
11 S. Yin, S. Liu, H. Zhang, S. Jiao, Y. Xu, Z. Wang, X. Li, L. Wang
and H. Wang, ACS Appl. Mater. Interfaces, 2021, 13, 20233–
20239.
Conclusions
In conclusion, using the concept of metal–organic nanohybrids, 12 H. Tan, J. Tang, J. Kim, Y. V. Kaneti, Y.-M. Kang, Y. Sugahara
the surface of pre-synthesized AuPd LCs was modied with TA
and Y. Yamauchi, J. Mater. Chem. A, 2019, 7, 1380–1393.
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Paper
Journal of Materials Chemistry A
13 X. Yan, Y. Jia, K. Wang, Z. Jin, C.-L. Dong, Y.-C. Huang, 36 S. Yin, Z. Wang, H. Zhang, C. Li, H. Yu, Y. Xu, X. Li, L. Wang
J. Chen and X. Yao, Carbon Energy, 2020, 2, 452–460. and H. Wang, Chem. Eng. J., 2020, 399, 125810.
14 X.-T. Wu, L.-J. Peng, K. Xiao, N. Li and Z.-Q. Liu, Chem. 37 D. Chen, Y. Wang, D. Liu, H. Liu, C. Qian, H. He and J. Yang,
Commun., 2021, 57, 5258–5261. Carbon Energy, 2020, 2, 443–451.
15 X.-T. Wang, T. Ouyang, L. Wang, J.-H. Zhong, T. Ma and 38 H. Yu, Z. Wang, S. Yin, C. Li, Y. Xu, X. Li, L. Wang and
Z.-Q. Liu, Angew. Chem., Int. Ed., 2019, 131, 13425–13430. H. Wang, ACS Appl. Mater. Interfaces, 2020, 12, 436–442.
16 Y. Yang, G. Chen, R. Zeng, A. M. Villarino, F. J. DiSalvo, 39 H. Wang, Y. Li, D. Yang, X. Qian, Z. Wang, Y. Xu, X. Li, H. Xue
R. B. van Dover and H. D. Abruna, J. Am. Chem. Soc., 2020,
142, 3980–3988.
17 H. Lv, D. Xu, L. Sun, J. Henzie, S. L. Suib, Y. Yamauchi and
B. Liu, ACS Nano, 2019, 13, 12052–12061.
and L. Wang, Nanoscale, 2019, 11, 5499–5505.
40 M. Li, Z. Zhao, Z. Xia, Y. Yang, M. Luo, Y. Huang, Y. Sun,
Y. Chao, W. Yang, W. Yang, Y. Yu, G. Lu and S. Guo, ACS
Catal., 2020, 10, 3018–3026.
18 M. Iqbal, Y. Kim, C. Li, B. Jiang, T. Takei, J. Lin, B. Yuliarto, 41 X. Jiang, Y. Xiong, R. Zhao, J. Zhou, J.-M. Lee and Y. Tang,
Y. Bando, J. Henzie and Y. Yamauchi, ACS Appl. Mater.
Interfaces, 2019, 11, 36544–36552.
19 M. Luo, Z. Zhao, Y. Zhang, Y. Sun, Y. Xing, F. Lv, Y. Yang,
Nano Res., 2020, 13, 2691–2696.
42 Y. Jiang, Y. Guo, Y. Zhou, S. Deng, L. Hou, Y. Niu and T. Jiao,
ACS Omega, 2020, 5, 14805–14813.
X. Zhang, S. Hwang, Y. Qin, J. Y. Ma, F. Lin, D. Su, G. Lu 43 Y. F. Xu, X. Y. Li, J. H. Gao, J. Wang, G. Y. Ma, X. D. Wen,
and S. Guo, Nature, 2019, 574, 81–85. Y. Yang, Y. W. Li and M. Y. Ding, Science, 2021, 371, 610–613.
20 H. Zhang, X. Qiu, Y. Chen, S. Wang, S. E. Skrabalak and 44 W. Zhang, B. Huang, K. Wang, W. Yang, F. Lv, N. Li, Y. Chao,
Y. Tang, Small, 2020, 16, e1906026.
21 L. Sahoo and U. K. Gautam, ACS Appl. Nano Mater., 2020, 3,
8117–8125.
22 S. Yin, Z. Wang, S. Liu, S. Jiao, W. Tian, Y. Xu, X. Li, L. Wang
and H. Wang, Nanoscale, 2021, 13, 3208–3213.
23 F. Gao, Y. Zhang, F. Ren, Y. Shiraishi and Y. Du, Adv. Funct.
Mater., 2020, 30, 2000255.
24 T. J. Wang, F. M. Li, H. Huang, S. W. Yin, P. Chen, P. J. Jin
and Y. Chen, Adv. Funct. Mater., 2020, 30, 2000534.
P. Zhou, Y. Yang, Y. Li, J. Zhou, W. Zhang, Y. Du, D. Su and
S. Guo, Adv. Energy Mater., 2020, 11, 2003192.
45 J. E. Sulaiman, S. Zhu, Z. Xing, Q. Chang and M. Shao, ACS
Catal., 2017, 7, 5134–5141.
46 Q. Xue, G. Xu, R. Mao, H. Liu, J. Zeng, J. Jiang and Y. Chen, J.
Energy Chem., 2017, 26, 1153–1159.
47 J. Wei, Y. Liang, Y. Hu, B. Kong, G. P. Simon, J. Zhang,
S. P. Jiang and H. Wang, Angew. Chem., Int. Ed., 2016, 55,
1355–1359.
25 R. Chang, L. Zheng, C. Wang, D. Yang, G. Zhang and S. Sun, 48 Y. Peng, Q. Liu, B. Lu, T. He, F. Nichols, X. Hu, T. Huang,
Appl. Catal., B, 2017, 211, 205–211.
26 S. Mondal and C. R. Raj, ACS Appl. Mater. Interfaces, 2019, 11,
14110–14119.
G. Huang, L. Guzman, Y. Ping and S. Chen, ACS Catal.,
2021, 11, 1179–1188.
49 Y. Shi, Y. Ji, J. Long, Y. Liang, Y. Liu, Y. Yu, J. Xiao and
B. Zhang, Nat. Commun., 2020, 11, 3415.
27 M. Iqbal, Y. V. Kaneti, J. Kim, B. Yuliarto, Y. M. Kang,
Y. Bando, Y. Sugahara and Y. Yamauchi, Small, 2019, 15, 50 Q. Xue, J. Bai, C. Han, P. Chen, J.-X. Jiang and Y. Chen, ACS
e1804378. Catal., 2018, 8, 11287–11295.
28 X. Peng, D. Lu, Y. Qin, M. Li, Y. Guo and S. Guo, ACS Appl. 51 S.-i. Yamazaki, M. Asahi, N. Taguchi, T. Ioroi, Y. Kishimoto,
Mater. Interfaces, 2020, 12, 30336–30342.
H. Daimon, M. Inaba, K. Koga, Y. Kurose and H. Inoue, ACS
Catal., 2020, 10, 14567–14580.
52 Y. Wang, S. Chen, S. Zhao, Q. Chen and J. Zhang, J. Mater.
Chem. A, 2020, 8, 15845–15852.
53 L. Fan, Y. Ma, Y. Su, R. Zhang, Y. Liu, Q. Zhang and Z. Jiang,
RSC Adv., 2015, 5, 107777–107784.
54 Y. Song, T. Wang, J. Sun, Z. Wang, Y. Luo, L. Zhang, H. Ye
and X. Sun, ACS Sustainable Chem. Eng., 2019, 7, 14368–
14372.
29 H. Yu, T. Zhou, Z. Wang, Y. Xu, X. Li, L. Wang and H. Wang,
Angew. Chem., Int. Ed., 2021, 60, 12027–12031.
30 G. Zhang, J. Zhou, J. Liu, T. Ma, Y. Chen and C. Xu,
Nanotechnology, 2021, 32, 095401.
31 Y. Feng, Q. Shao, F. Lv, L. Bu, J. Guo, S. Guo and X. Huang,
Adv. Sci., 2019, 7, 1800178.
32 G. Yang, Y. Wang, L. Xu, Y. Li, L. Li, Y. Sun, Z. Yuan and
Y. Tang, Chem. Eng. J., 2020, 379, 122230.
33 C. Chen, H. Su, L.-N. Lu, Y.-S. Hong, Y. Chen, K. Xiao, 55 J. Guo, Y. Ping, H. Ejima, K. Alt, M. Meissner,
T. Ouyang, Y. Qin and Z.-Q. Liu, Chem. Eng. J., 2021, 408,
127814.
34 L. Du, G. Zhang, X. Liu, A. Hassanpour, M. Dubois,
A. C. Tavares and S. Sun, Carbon Energy, 2020, 2, 561–581.
35 S. Liu, Z. Wang, H. Zhang, S. Wang, P. Wang, Y. Xu, X. Li,
J. J. Richardson, Y. Yan, K. Peter, D. von Elverfeldt,
C. E. Hagemeyer and F. Caruso, Angew. Chem., Int. Ed.,
2014, 53, 5546–5551.
56 X. Jiang, X. Qiu, G. Fu, J. Sun, Z. Huang, D. Sun, L. Xu, J. Zhou
and Y. Tang, J. Mater. Chem. A, 2018, 6, 17682–17687.
L. Wang and H. Wang, ACS Sustainable Chem. Eng., 2020, 57 G. Deng, T. Wang, A. A. Alshehri, K. A. Alzahrani, Y. Wang,
8, 14228–14233.
H. Ye, Y. Luo and X. Sun, J. Mater. Chem. A, 2019, 7,
21674–21677.
This journal is © The Royal Society of Chemistry 2021
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