Au/Pt Bimetallic Nanoparticle Decorated Microparticle Hybrid Catalyst System for Heterogeneous Hydrogenation of Styrene

Article abstract of DOI:10.1007/s10562-021-03599-4

Poly(methacryloyloxy quinoline) microparticles were synthesized and used as reducing and stabilizing agents to prepare Au/Pt bimetallic nanoparticle (NP) decorated microparticle (MP) hybrid catalyst systems. These newly reported hybrid catalyst systems were used for reduction of styrene into ethylbenzene. Gold precursor was essential to prepare bimetallic NPs due to its great interaction with PMAQ resulting in the reduction to AuNPs on the surface of PMAQ MPs. Pt is also contrubute to NP formation thanks to this superior interaction between Au and PMAQ MPs. The bimetallic nanoparticle contents on the PMAQ MPs were determined as Au_0.85Pt_0.15 via XRD analysis. Au and Pt amounts were also determined with ICP-MS analysis. Although the metal amount in the sample was quite low, the catalytic effect was remarkable for hybrid system. AuNP decorated MPs had no catalytic activity for the reduction of styrene. Thus, it is clear that Pt was the active part of hybrid catalyst system for this reaction. On the other hand, gold precursor had been determined as crucial for the simultaneous synthesis of bimetallic NP decorated MPs as well. Graphic Abstract: New microparticles decorated with bimetallic nanoparticles have been synthesized and used effectively as a catalyst systems in the hydrogenation of styrene. While it is reported in the literature that such particles have successful catalytic activity in various oxidations, our particles stand out with reducing activities, reusabilities and easy production/removal properties. [Figure not available: see fulltext.]

Full text of DOI:10.1007/s10562-021-03599-4

Catalysis Letters
https://doi.org/10.1007/s10562-021-03599-4
Au/Pt Bimetallic Nanoparticle Decorated Microparticle Hybrid Catalyst
System for Heterogeneous Hydrogenation of Styrene
Zeynep Dikmen1 · Hakan Ünver2 · Vural Bütün3
Received: 7 January 2021 / Accepted: 10 March 2021
© The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature 2021
Abstract
Poly(methacryloyloxy quinoline) microparticles were synthesized and used as reducing and stabilizing agents to prepare Au/
Pt bimetallic nanoparticle (NP) decorated microparticle (MP) hybrid catalyst systems. These newly reported hybrid catalyst
systems were used for reduction of styrene into ethylbenzene. Gold precursor was essential to prepare bimetallic NPs due
to its great interaction with PMAQ resulting in the reduction to AuNPs on the surface of PMAQ MPs. Pt is also contrubute
to NP formation thanks to this superior interaction between Au and PMAQ MPs. The bimetallic nanoparticle contents on
the PMAQ MPs were determined as Au0.85Pt0.15 via XRD analysis. Au and Pt amounts were also determined with ICP-MS
analysis. Although the metal amount in the sample was quite low, the catalytic efect was remarkable for hybrid system.
AuNP decorated MPs had no catalytic activity for the reduction of styrene. Thus, it is clear that Pt was the active part of
hybrid catalyst system for this reaction. On the other hand, gold precursor had been determined as crucial for the simultane-
ous synthesis of bimetallic NP decorated MPs as well.
Graphic Abstract
New microparticles decorated with bimetallic nanoparticles have been synthesized and used efectively as a catalyst systems
in the hydrogenation of styrene. While it is reported in the literature that such particles have successful catalytic activity in
various oxidations, our particles stand out with reducing activities, reusabilities and easy production/removal properties.
Keywords Hybrid catalyst · Au/Pt bimetallic NPs · Microparticle · Hydrogenation · Polymer composites
* Vural Bütün
vbutun@ogu.edu.tr
1 Introduction
1
Department of Biomedical Engineering, Faculty
of Engineering, Eskisehir Osmangazi University,
26040 Eskisehir, Turkey
Hybrid systems consisting of metal nanoparticles (MNPs)
and polymers are promising candidates for many applications
including catalysis of organic reactions [1–4]. Polymers are
quite convenient to prepare creative hybrid materials in dif-
ferent physical forms and shapes such as microgel-MNP [5],
2
3
Department of Chemistry, Faculty of Science, Eskisehir
Technical University, 26470 Eskisehir, Turkey
Department of Chemistry, Facullty of Science and Letters,
Eskisehir Osmangazi University, 26040 Eskisehir, Turkey
Vol.:(0123456789)
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Z. Dikmen et al.
micelle-MNP [6], polymer stabilizer-MNP [7], nanofber-
MNP [8] hybrid systems. Polymeric structures around the
catalyst MNPs provide essential properties for the catalytic
reactions such as extended lifetime, recycling of the cata-
lysts and stability in the medium [9, 10]. Gold nanoparticles
embedded into poly(N-isopropylacrylamide) particles result
in increased chemical stability and these hybrid particles are
reported to be convenient catalysts for oxidation of benzyl
alcohol, reduction of 4-nitrophenol, and homocoupling of
phenylboronic acid [11]. Low Pt containing PtNP/poly(a-
terthiophene) hybrid material efciently catalyses hydrogen
evolution reaction [12]. Convenient functional groups acting
as active sites for binding metal NPs are crucial to avoid
from limitation of their potential application as catalyst [13].
In general, due to weak interaction of metal and polymer
functional groups, polymer stabilized nanoparticle catalyst
systems were reported with the usage of additional support-
ing ligands in order to get strong metal–polymer interactions
[14]. The way to avoid from such ligand-additives is to use
polymers containing functional groups that can interact well
with metal nanoparticles.
bimetallic NPs was studied to enhance the catalytic activ-
ity. Although Pt and/or Pt2+ ions were embeded by PMAQ
microparticles (MPs), gold was reduced without use of any
reducing agent. Gold ions were reduced by PMAQ MPs con-
taining strong chelating 8-hydroxy quinoline and resulted
with formation of both seeds and raspberry-like AuNPs [24].
As a result of interesting interaction of gold with PMAQ
MPs, gold was also used as an anchor site for the forma-
tion of Au/Pt bimetallic NPs on MPs in this study. UV light
assisted photocatalytic synthesis of Au/Pt bimetallic NPs
decorated PMAQ MPs were synthesized and used as hybrid
systems. Au:Pt:polymer ratios were determined by ICP-MS
analysis. Au and Pt contents of the hybrid particles were
determined to be 7.50 wt% and 4.42 wt%, respectively. The
MPs and hybrid particles were successfully characterized
by scanning electron microscopy (SEM) analyzes. These
new hybrid catalysts with very low content of metal exhibit
comparable efects for the reduction of styrene into ethyl
benzene. Even though bimetallic Au/Pt NP decorated MPs
exhibited good catalytic efect, AuNP decorated MPs did
not show any catalytic efect for styrene reduction. As a
result, Pt was responsible for catalytic activity while Au was
responsible from formation of bimetallic NPs.
A diferent approach is to combine diferent metals to
get bimetallic nanosystems which enhances catalytic and
electronic properties of catalyst systems, resulting from
much more possibilities in shape and structure [15, 16].
The enhancement mechanism is attributed to organization of
atoms within the particle and miscellaneous distribution of
each metal atoms. Hybrid materials combined with polymer
and bimetallic nanoparticles (NPs) are promising materials
for various applications [13, 17, 18]. Although Au/Pt∙NP
catalyst systems are used for aerobic glucose oxidation [19,
20], methanol oxidation [21] and formic acid oxidation [22,
23], polymer supported Au/PtNP hybrid catalyst for the
hydrogenation of styrene into ethyl benzene has not been
reported yet. Without requiring any additional supporting
ligands, polymer-MNP hybrid catalyst system can be pro-
duced by using poly(methacryloyloxyquinoline) (PMAQ) as
polymer source which acts as a stabilizer/host as well as a
supporting ligand resulting from 8-hydroxyquinoline-based
anchor sites for interaction with metals. Synthesis of PMAQ
MPs, its optical response to metal ions and gold nanoparticle
formation stages are reported in our previous study [24].
Eventhough there are a few reports on metal NP decorated
microparticle synthesis [25, 26], their usage as catalyst sys-
tems are very limited in the literature [27]. Au/Ag bimetal-
lic NP decorated cyclophosphazene hybrid microspheres
have been used for the reduction of 4-nitro phenol with an
enhanced catalytic activity [13]. Pt on AuNP bimetallic
catalyst was reported to have higher catalytic activity due to
enhanced Pt mass-activity [28].
2 Experimental
2.1 Materials
Gold (III) chloride hydrate (HAuCl4∙xH2O, 99.999% trace
metals basis), potassium tetrachloroplatinate (II) (K2PtCl4,
99.99% trace metals basis), triethylamine (Et3N≥99.5%),
magnesium sulfate (MgSO4 ≥ 99.5%), dichloromethane
(DCM, used after drying 1 week with molecular sieve),
poly(vinyl alcohol) (PVA, 89.000–98.000, 99+ % hydro-
lyzed), 2,2′-azobis(2-methylpropionitrile) (AIBN, 98%),
sodium dodecyl sulfate (SDS ≥ 99.0%), diethyl ether
(≥ 99.5%), chloroform (CHCl3, ≥ 99.5%), ethylene glycol
dimethacrylate (98%), sodium chloride (NaCl, ≥ 99.0%),
8-hydroxy quinoline (8HQ, 99.0%), methacryloyl chloride
(97%), styrene (≥ 99.0%), ethyl benzene (≥ 99.0%) were
purchased from Sigma-Aldrich. HNO3 (65%), HCl (30%)
and H2O2 (30%) were purchased from Merck Suprapur and
used for ICP-MS analysis. Distilled water was used for all
experiments.
2.2 Characterization and Instrumentation
The samples were investigated with transmission electron
microscopy (TEM) under 100 kV accelerating voltage by
performing on a Hitachi HT7800 TEM. SEM images were
captured at accelerating voltages of 1–10 kV on a Hitachi
Regulus 8230. The samples were coated with Au–Pd (Leica
Herein, we report the synthesis of PMAQ microparti-
cles decorated with Au/Pt NPs and their successful cata-
lytic activity in reducing of styrene. In-situ formation of
1 3

Au/Pt Bimetallic Nanoparticle Decorated Microparticle Hybrid Catalyst System for…
EM ACE600). ICP-MS analytes were prepared with a SK-15
high temperature and pressure rotor in the Milestone Ethos
Up microwave for analysis. Ag–Au–Pt–Pd alloy method was
used by treatment with 3 mL HNO3, 6 mL HCl and 1 mL
H2O2. The solution samples were diluted 4000 times with
distilled water before analysis. Thermo iCAP RQ induc-
tively coupled plasma-mass spectrometer (ICP-MS) was
used to analyze the samples. Au and Pt elemental standards
were used to prepare calibration curves (using 5, 10, 25,
50, 100 ppb concentrations). 1H NMR spectroscopy meas-
urements were recorded on Jeol ECZ 500R spectrometer
at room temperature. The catalytic hydrogenation percen-
tiles were determined using Thermo Finnigan Trace GC/
GC–MS device attached with Permabond SE-54-DF-0.25
25 m×0.32 mm ID column with FID detector and He car-
rier gas.
was heated to reaction temperature and flled with desired
amount of reductive gas. After the reaction time ended, the
reactor was discharged and a few drops of reaction mixture
was diluted with pure reaction solvent, then analyzed with
gas chromatography (GC) using appropriate GC-analyzing
method.
3 Results and Discussion
Synthesis of PMAQ microparticles acting as both reducing
agent and stabilizer for gold in diferent evolution stages in
dark and under UV-light excitation was reported in our pre-
vious study. We ofered an evolution for formation of gold
nanoparticles in solution after leaving from the surface of
PMAQ MPs [24]. Usage of gold precursor with platinum
precursor results with bimetallic NP formation on PMAQ
microparticles. However Pt2+ addition to the MP dispersion
does not result with nanoparticle formation as supported
with SEM, TEM and XRD analysis. Pt2+ interaction with
PMAQ via complexation results with fuorescent quench-
ing of MPs [24]. SEM images of PMAQ MPs, Pt2+/PMAQ
MPs and Au/Pt NP decorated MPs are given in Fig. 1. The
surface morphology of bare PMAQ MPs given in SEM
images (Fig. 1a, b, c) is quite similar to platinium inter-
acted MPs surface. In the absence of gold precursor, K2PtCl4
addition to the PMAQ MPs dispersion is not resulted with
PtNP formation as given in SEM images (Fig. 1d, e, f). It
can be clearly seen that there is not nanoparticular forma-
tion after platinium treatment. Amorphous polymer peak
in the XRD pattern of Pt2+/PMAQ given in Fig. 2a proves
that no PtNPs are formed. It is assumed that gold act as
seed in the formation of Au/Pt bimetallic NPs. Herein, we
also observed raspberry like nanoparticle formation on
MPs proving action of gold as seed. Eventhough spherical
AuNP formation on MPs is observed after HAuCl4∙3H2O
addition to the PMAQ MPs dispersion (Fig. 3a, b), addition
of K2PtCl4 and HAuCl4∙3H2O together results with cubic
nanoparticle formation in the solution. So, Pt2+ addition to
the reducing media resulted in the formation of nanocubes
instead of spherical NPs. Because of the low contrast of
these nanocubes possibly resulting from nanoplatelet struc-
ture of the material, the particles on the surface are not as
clear as AuNPs on MPs (Fig. 3b). TEM images of bime-
tallic nanocubes in solution phase and bimetallic NPs on
the surface of MPs are given in Fig. 3c, d, and Fig. 3e, f,
respectively. Nanocubes in solution phase were separated
via centrifugation at 1000 rpm. Au/Pt NP decorated MPs
were washed three times and centrifuged before catalysis
experiments for further SEM, XRD analysis.
2.3 Synthesis of MAQ Monomer
MAQ monomer was synthesized as reported [24].
8-Hydroxy quinoline (43.5 g, 0.30 mol) and triethylamine
(85.5 mL, 0.62 mol) were dissolved in dried DCM (300 mL).
The mixture was cooled to 0 °C in an ice bath followed
by (25.83 mL, 0.26 mol) methacryloyl chloride addition by
dropwise. After addition of methacryloyl chloride, the mix-
ture was stirred at room temperature overnight. Then solvent
was evaporated and crude product was crystalized in diethyl
ether [29]. Synthesis of PMAQ MPs via mini-suspension
polymerization and AuNPs coated microparticles were car-
ried out as reported before [24].
2.4 Preparation of Au/Pt NP Decorated MPs
PVA-SDS stabilized microparticles (0.1 g, MP1) were dis-
persed in 5.0 mL distilled water. Metal salt solutions (0.1 M,
5.0 mL HAuCl4∙3H2O and 0.1 M, 5.0 mL KPtCl4) were
added dropwise with syringe pumps (5.0 mL/min) under UV
light excitation, reaction was carried out at room temperature
by stirring for 30 min. Then, the reaction was quenched by
precipitation of suspensions via centrifugation at 1000 rpm
to eliminate free metal nanoparticles from microparticles.
2.5 Catalytic Hydrogenation Reactions
The catalytic experiments were conducted in stainless-steel
100 mL high-pressure Parr 4545 reactor equipped with two
sapphire windows for visual checking and a temperature
controller. In a typical experiment, the calculated amounts
of substrate (styrene), Au/Pt NP decorated MP catalyst and a
magnetic stirrer was introduced into a glass tube containing
reaction solvent and a magnetic stirrer, then the tube was put
into the reactor. The reactor was closed tightly and purged
gently a few times with hydrogen gas (H2). The reactor
XRD spectra of Pt2+/PMAQ, AuNPs decorated MPs
and Au/Pt NPs decorated MPs are given in Fig. 2a, b, c,
respectively. Au crystal formation was determined as to
1 3

Z. Dikmen et al.
Fig. 1 SEM images of PMAQ MPs (a,b,c), PMAQ/Pt2+ MPs (d,e,f) and Au/Pt NPs decorated MPs (g,h,i)
be face centered cubic (fcc) form. XRD spectrum of the
Au/Pt coated MPs given in Fig. 2 proves the formation of
Au0.85Pt0.15 alloy bimetallic particles which is good ftting to
reference peaks (ICSD: 01-085-4819). As we reported in our
previous study [24], gold seeds were formed on the surface
of MPs which act as an anchor point for further particle for-
mation (i.e. raspberry-like particles or bimetallic nanoparti-
cles) via Ostwald ripening phenomenon. It is also observed
that addition of gold was crucial for further bimetallic par-
ticle formation. Nanoparticle formation was not observed
with platinium addition into MPs dispersion and Pt crystal
formation was not also observed by XRD pattern.
showed that PMAQ MPs had a good complexation with
platinium cation in quite short time (15 min). The possible
complexation is depicted in Fig. 4. Low ammount of Pt in
bimetallic system dramatically changed the catalytic char-
acter of the hybride system. Since K2PtCl4 addition was not
resulted with nanoparticle formation as indicated by both
SEM, TEM and XRD studies, the catalytic activity of Pt2+/
PMAQ MPs complex could not be compared with Au/Pt
NPs on MPs catalyst. Platinium ratio of the complex Pt2+/
PMAQ MPs was measured as to be 4.42% that is also given
in the Table 1.
AuNP decorated MPs were also examined as catalyst for
the reduction of styrene into ethyl benzene. Despite the high
gold ratio of the AuNPs/PMAQ hybrid catalyst, the system
did not exhibit catalytic activity towards styrene reduction.
It is indicating that the Pt is the resposive part of the hybride
catalyst even quite low Pt content.
Metal amounts in the samples were determined by
ICP-MS analysis as given in Table 1. In the hybrid cata-
lyst, amount of Pt and Au were 2.63% and 7.5% by weight,
respectively. Pt-free AuNPs decorated MPs containing
12.3% gold did not act as a catalyst for styrene reduction
as given in Table 2. The amount of Pt in Pt2+/PMAQ MPs
complex was also measured as 4.42%. This amount of Pt
The hydrogenation reactions were carried out over
styrene reduction to ethyl benzene and the scheme of the
1 3

Au/Pt Bimetallic Nanoparticle Decorated Microparticle Hybrid Catalyst System for…
Fig. 2 XRD patterns of amorphous Pt2+/PMAQ MPs (a), AuNPs on MPs (b) Au0.85Pt0.15 bimetallic NPs on MPs (c) and XRD patterns of
Au0.85Pt0.15 bimetallic NPs good ftting with the reference peaks of Au0.85Pt0.15 (ICSD: 01-085-4819) (d)
reaction was given in Fig. 4. Au/Pt NPs are efectively used
as catalyst for lots of oxidation reactions. Usage of Au/Pt
NPs decorated MPs catalyst in the reduction of styrene as
a model reaction is reported in this study. Catalytic activi-
ties of Au/Pt decorated MPs were studied in diferent reac-
tion conditions. The catalytic activities of AuNP decorated
MPs and only PMAQ MPs were also tested (Table 2, Entries
15–16). Due to AuNP/MPs hybrid system and PMAQ MPs
did not exhibit any catalytic activity, Pt component of the
catalyst was responsible for the catalytic efect of the Au/
Pt-MP hybrid catalyst. Thus, the amount of catalyst was cal-
culated according to the Pt content of Au/Pt NPs decorated
MPs catalyst system.
number/turn over frequency (TON/TOF) value was cal-
culated as 129 under the same conditions (Entry 1). The
order of efectivity of other polar protic solvents were
ethanol (C2H5OH), water (H2O) and iso-propyl alcohol
(i-PrOH) and the calculated ethyl benzene formations were
95.2, 92.5 and 5.6%, respectively (Entries 2–4). The reason
for the lowest conversion rate among polar protic solvents
was dedicated to the lowest polar nature of iso-propyl alco-
hol (i-PrOH) among the other polar protic solvents. It was
observed that the synthesized catalyst systems were nearly
inefective in polar aprotic (CH3CN and THF) and apolar
(n-Hexane) solvents and the conversion values were deter-
mined as to be between 0.5 and 2.4% (Entries 5–7). As a
result, the most appropriate reaction media was found to be
CH3OH. After the detection of the most suitable solvent,
experiments were conducted in methanol between 30 and
50 °C to determine the optimum reaction temperature of
styrene hydrogenation. It was observed that the product
formation is directly related with the reaction tempera-
ture. Ethyl benzene formation slowly increased from 3.2
to 6.8% at 40 °C (Entries 8–9). Interestingly, the conver-
sion rate dramatically increased to quantitative level at
50 °C with 100% product formation (Entry 1). This means
that, the activity of catalyst is dramatically increased at
this temperature. Hydrogen pressure efect investigations
was conducted between 10 and 30 bar and it was found
Solvent, temperature, hydrogen gas pressure and sub/cat
ratio efects were tested to determine the optimum reac-
tion conditions and obtained results are given in Table 2.
It was found that, the tested nanoparticles were efcient
metal catalysts for styrene reduction under mild conditions
as 50 ºC, 30 bar H2 and 1 h reaction time. To test the sol-
vent efect, catalytic experiments were carried out in seven
diferent reaction media including polar protic (CH3OH,
C2H5OH, i-PrOH and H2O), polar aprotic (CH3CN, THF)
and apolar (n-Hexane) solvents (Table 2, Entries 1–7).
According to the catalytic activity results the most suit-
able solvent group was determined as polar protic solvents
and the highest ethyl benzene conversion was reached in
methanol (CH3OH) with 100% conversion and turn over
1 3

Z. Dikmen et al.
Fig. 3 TEM images of AuNPs
on surface and in solution (a,b),
Au–Pt nanocubes forming in the
solution (c,d), Au/Pt nanoparti-
cle coated MPs (e,f)
Table 1 ICP-MS results of diluted Au/Pt NPs decorated MPs, AuNPs decorated MPs and Pt2+/PMAQ MPs
Analyte
Concentration SDa (µg L−1) (n=3)
Mean (µg L−1
)
wt%
7.52
2.63
12.30
4.42
Au
Pt
Au [24]
Pt
49.57 0.65
16.84 0.31
341.67 14.27
20.94 0.07
48.82 0.10
17.63 0.47
348.83 7.11
21.18 0.17
48.37 0.55
16.99 0.16
377.32 21.38
20.91 0.10
48.92 0.43
17.15 0.31
355.94 14.26
21.01 0.11
that the product formation increased with increasing H2
pressure and the maximum product formation was reached
under 30 bar H2. In the fnal step, to test the ns/nc ratio,
experiments were conducted with ns/nc = 129, 258 and
386. According to the results, the highest product forma-
tion was observed at ns/nc = 129 with the similar TON/
TOF values. Catalytic activity of Pt2+/PMAQ MPs was
determined in the same condition and TON/TOF value
was determined as 772. Pt2+/PMAQ MPs complex was
also observed as an efective catalyst for styrene reduc-
tion. Control and blank experiments were also conducted
with AuNP decorated MPs and pure PMAQ MPs support
and only trace amount (< 1%) of product formations was
observed (Entries 14–16).
4 Conclusion
Novel Au/Pt bimetallic NP decorated PMAQ MPs were
successfully synthesized in quite short time under UV-light
excitation and their catalytic activities in the reduction of
styrene were investigated. Even though AuNPs decorated
MPs did not have any catalytic activity in styrene reduction,
1 3

Au/Pt Bimetallic Nanoparticle Decorated Microparticle Hybrid Catalyst System for…
Table 2 Solvent efect on the
hydrogenation of styrene by Au/
Pt NPs decorated MP catalyst
system
Entry a,b
Solvent
T (oC)
P (H2, Bar)
Sub/cat (ns/nc)
Yield (%)
TON
TOF (h−1
)
1
2
3
4
5
6
7
8
CH3OH
C2H5OH
H2O
i-PrOH
CH3CN
THF
n-Hexane
CH3OH
CH3OH
CH3OH
CH3OH
CH3OH
CH3OH
CH3OH
CH3OH
CH3OH
CH3OH
50
50
50
50
50
50
50
30
40
50
50
50
50
50
50
50
50
30
30
30
30
30
30
30
30
30
10
20
30
30
30
30
30
30
129
129
129
129
129
129
129
129
129
129
129
258
386
129
129
129
772
100
95.2
92.5
5.6
2.4
0.8
0.5
3.2
6.8
129
123
119
6
3
1
1
4
9
23
26
6
4
0
0
0
772
129
123
119
6
3
1
1
4
9
23
26
6
4
0
0
0
772
9
10
11
12
13
14c
15d
16e
17f
18.2
20.5
5.6
3.6
Trace
Trace
Trace
100
aReaction cond.: nPt =6.77×10−7 mol, nstyrene =Vsolv. =10 mL, t=60 min
bDetermined with GC
cWithout catalyst
dWith AuNP decorated MP catalyst
eWith only PMAQ polymer support
fPMAQ-Pt complex catalyst, nPt =1.13×10−6 mol
Fig. 4 Illustration of NP formation on MPs and styrene hydrogenation reaction with Au/Pt NP decorated MP catalyst system
Au/Pt bimetallic nanoparticle decorated MPs had good cata-
lytic activity in the reduction of styrene. These new bime-
tallic hybrid particles and Pt2+/PMAQ MPs can be promis-
ing catalyst systems due to their advantages on their easily
removing abilities from mixtures. Herein, styrene conversion
into ethyl benzene was successfully carried out under mild
conditions with these talented particles. Solvent, tempera-
ture, sub/cat and pressure of H2 gas efects were also inves-
tigated in detail. It was experienced that the best results were
obtained at 50 °C, 30 bar H2 and 1 h reaction time in polar
1 3

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15. Zaleska-Medynska A, Marchelek M, Diak M, Grabowska E
(2016) Noble metal-based bimetallic nanoparticles: the efect of
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the reduction of styrene. Immobilization of these efective
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