Catalytic properties of reduced graphene oxide deposited on aluminum and magnesium oxides in acetylene hydrogenation
The catalytic properties of reduced graphene oxide (rGO) deposited on aluminum and magnesium oxides were investigated in acetylene hydrogenation. Catalysts with different rGO loadings were prepared by impregnating γ-Al₂O₃ and MgO with aqueous graphene oxide suspensions, followed by reduction in hydr...
Збережено в:
| Дата: | 2025 |
|---|---|
| Автори: | , , |
| Формат: | Стаття |
| Мова: | Англійська |
| Опубліковано: |
V.P. Kukhar Institute of Bioorganic Chemistry and Petrochemistry of the National Academy of Sciences of Ukraine
2025
|
| Теми: | |
| Онлайн доступ: | https://kataliz.org.ua/index.php/journal/article/view/128 |
| Теги: |
Додати тег
Немає тегів, Будьте першим, хто поставить тег для цього запису!
|
| Назва журналу: | Catalysis and petrochemistry |
| Завантажити файл: |  |
Репозитарії
Catalysis and petrochemistry| _version_ | 1872009072110206976 |
|---|---|
| author | Nosach, Viktoriia V. Bychko, Igor B. Strizhak , Peter Ye. |
| author_facet | Nosach, Viktoriia V. Bychko, Igor B. Strizhak , Peter Ye. |
| author_institution_txt_mv | [
{
"author": "Viktoriia V. Nosach",
"institution": "National University of “Kyiv-Mohyla Academy” 2 Hryhoriya Skovorody Str., Kyiv, 04655 Ukraine"
},
{
"author": "Igor B. Bychko",
"institution": "L.V. Pisarzhevskii Institute of Physical Chemistry of National Academy of Sciences of Ukraine 31 Nauky Avenue, Kyiv, 03028, Ukraine"
},
{
"author": "Peter Ye. Strizhak ",
"institution": "L.V. Pisarzhevskii Institute of Physical Chemistry of National Academy of Sciences of Ukraine 31 Nauky Avenue, Kyiv, 03028, Ukraine"
}
] |
| author_sort | Nosach, Viktoriia V. |
| baseUrl_str | https://kataliz.org.ua/index.php/journal/oai |
| collection | OJS |
| datestamp_date | 2025-12-28T17:23:30Z |
| description | The catalytic properties of reduced graphene oxide (rGO) deposited on aluminum and magnesium oxides were investigated in acetylene hydrogenation. Catalysts with different rGO loadings were prepared by impregnating γ-Al₂O₃ and MgO with aqueous graphene oxide suspensions, followed by reduction in hydrogen at 400 °C. The materials were characterized by FTIR, Raman spectroscopy, and SEM. FTIR spectra confirmed the successful deposition of rGO on both supports, and for MgO-based samples, FTIR also revealed partial hydration of surface Mg–O groups, forming Mg(OH)₂ and a hydroxide–graphene interfacial layer that improves anchoring and stabilizes the structure. Raman spectroscopy verified the formation of a graphene-based phase on both oxides and showed that the defect level of the deposited graphene remains constant with varying rGO loading. SEM analysis indicated that on MgO, rGO forms thin film-like structures and irregular folds that create partially covered regions, while on γ-Al₂O₃ it forms continuous films in some areas and isolated folds in others. Modification of γ-Al₂O₃ and MgO with rGO enhanced catalytic activity in acetylene hydrogenation, with the highest rates observed for samples with low rGO content. Both rGO/Al₂O₃ and rGO/MgO exhibited full (100 %) selectivity to ethylene in the 250–400 °C range. The improved performance is attributed to rGO-derived surface structures that ensure effective contact between carbon and oxide phases and facilitate activation of acetylene and hydrogen. Overall, the catalytic behavior of rGO-modified oxides is governed by the acid–base properties of the support and the structural features of the deposited graphene layer, which determine the activation temperature and thermal stability of the system. |
| doi_str_mv | 10.15407/kataliz2025.36.057 |
| first_indexed | 2026-03-12T15:50:23Z |
| format | Article |
| fulltext |
Каталіз та нафтохімія, 2025, №36 57
Catalysis and Petrochemistry, 2025, 36
UDC 547.314.2:546.62-311
https://doi.org/10.15407/kataliz2025.36.057
Catalytic properties of reduced graphene oxide deposited on aluminum and
magnesium oxides in acetylene hydrogenation
Viktoriia V. Nosach 1, 2, Igor B. Bychko 1, Peter Ye. Strizhak 1
1 L.V. Pisarzhevskii Institute of Physical Chemistry of National Academy of Sciences of Ukraine
31 Nauky Avenue, Kyiv, 03028, Ukraine
2 National University of “Kyiv-Mohyla Academy”
2 Hryhoriya Skovorody Str., Kyiv, 04655 Ukraine, e-mail: victorynosach@gmail.com
The catalytic properties of reduced graphene oxide (rGO) deposited on aluminum and magnesium oxides
were investigated in acetylene hydrogenation. Catalysts with different rGO loadings were prepared by
impregnating γ-Al₂O₃ and MgO with aqueous graphene oxide suspensions, followed by reduction in hydrogen at
400 °C. The materials were characterized by FTIR, Raman spectroscopy, and SEM. FTIR spectra confirmed the
successful deposition of rGO on both supports, and for MgO-based samples, FTIR also revealed partial hydration
of surface Mg–O groups, forming Mg(OH)₂ and a hydroxide–graphene interfacial layer that improves anchoring
and stabilizes the structure. Raman spectroscopy verified the formation of a graphene-based phase on both oxides
and showed that the defect level of the deposited graphene remains constant with varying rGO loading. SEM
analysis indicated that on MgO, rGO forms thin film-like structures and irregular folds that create partially
covered regions, while on γ-Al₂O₃ it forms continuous films in some areas and isolated folds in others.
Modification of γ-Al₂O₃ and MgO with rGO enhanced catalytic activity in acetylene hydrogenation, with the
highest rates observed for samples with low rGO content. Both rGO/Al₂O₃ and rGO/MgO exhibited full (100 %)
selectivity to ethylene in the 250–400 °C range. The improved performance is attributed to rGO-derived surface
structures that ensure effective contact between carbon and oxide phases and facilitate activation of acetylene and
hydrogen. Overall, the catalytic behavior of rGO-modified oxides is governed by the acid–base properties of the
support and the structural features of the deposited graphene layer, which determine the activation temperature
and thermal stability of the system.
Keywords: reduced graphene oxide, aluminum oxide, magnesium oxide, acetylene hydrogenation,
carbocatalysis
Introduction
Catalytic hydrogenation of acetylene is an important reaction in both fine organic synthesis and
industrial chemistry, particularly in the production of high-purity ethylene [1, 2]. Achieving high
selectivity and activity in this reaction typically relies on oxide-supported catalysts such as γ-Al₂O₃,
SiO₂, MgO, and TiO₂. In recent years, increasing attention has been devoted to catalytic systems
modified with carbon nanostructures, which can improve the adsorption capacity and stability of active
centers [3, 4].
Among carbon-based materials, reduced graphene oxide (rGO) has attracted considerable interest
due to its high surface area, chemical stability, and ability to form hybrid interfaces with oxide supports
[5, 6]. The deposition of rGO layers on oxide surfaces promotes the formation of heterogeneous
interfaces that affect adsorption properties and surface reactivity [7]. Depending on the properties of
rGO, the catalytic properties of such hybrid systems may vary substantially.
Although most studies have focused on metal-loaded rGO catalysts, several works have
demonstrated that rGO itself can exhibit intrinsic catalytic activity in hydrogenation reactions without
metallic components [8, 9]. Metal-free reduced graphene oxide has been shown to catalyze the
hydrogenation of acetylene to ethylene and phenylacetylene to styrene. In addition, defect-rich or
N-doped rGO materials have demonstrated activity in the hydrogenation of styrene and terminal alkynes
https://doi.org/
58 Каталіз та нафтохімія, 2025, №36
Catalysis and Petrochemistry, 2025, 36
under mild conditions, highlighting the intrinsic catalytic potential of graphene-based systems [10].
These findings indicate that rGO can act not only as a conductive support but also as an active
component in hydrogenation processes.
The aim of this work is to reveal the effect of reduced graphene oxide deposited on γ-Al₂O₃ and
MgO on the catalytic properties of the resulting materials in the process of acetylene hydrogenation.
Structural and morphological characterization of the samples was performed using FTIR, Raman
spectroscopies, SEM analyses, and the temperature dependence of acetylene conversion was studied.
The obtained results provide a comparative analysis of γ-Al₂O₃- and MgO-supported systems,
highlighting the effect of the support on catalytic efficiency in acetylene hydrogenation.
Experiment
Catalyst samples with reduced graphene oxide were prepared by applying an aqueous suspension
of graphene oxide (GO) with different concentrations onto MgO (Novohim, 98.5 %) and Al₂O₃
(Yug Sintez, 99.0 %). The GO suspension was obtained by of graphite oxide (GrO), which had been
synthesized using a modified Hummers’ method followed by ultrasonic treatment [11]. Powders of
aluminum oxide and magnesium oxide with a particle size fraction of 0.25-0.5 mm were impregnated
with the suspension at a ratio of 1 mL per 1 g of support. After impregnation, the samples were kept at
60 °C for 3 h and then reduced in a hydrogen flow at 400 °C for 2 h. A series of samples containing GO
at 0.025 mg/g, 0.1 mg/g, and 1 mg/g were prepared. Each sample in the series was labeled according to
the type of support, the type of graphene material, and its concentration in wt. %, for example:
rGO(0.0025)/MgO, rGO(0.01)/Al₂O₃, etc.
The physicochemical properties of the obtained samples were investigated using Raman
spectroscopy, Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM),
and low-temperature nitrogen adsorption-desorption analysis. The morphology and spatial distribution
of elements in the samples containing reduced graphene oxide were examined by SEM using a MIRA3
Tescan microscope. FTIR spectra were recorded with a Perkin Elmer “Spectrum One” spectrometer in
the range of 400-4000 cm⁻1. Raman spectra were obtained at room temperature using a HORIBA
Jobin-Yvon T64000 confocal dispersive spectrometer equipped with an Ar-Kr laser (excitation
wavelength 488 nm, laser power 125 mW).
The catalytic activity of the samples in the acetylene hydrogenation reaction was studied under
flow conditions using chromatographic control of the composition of the reaction mixture and the
conversion products. The analysis was performed using a self-made assembly gas chromatograph
equipped with a thermal conductivity detector and a PoraPak S chromatographic column. The catalyst
was placed in a fixed-bed flow reactor between two layers of purified quartz. The acetylene
hydrogenation reaction was carried out in the temperature range of 50-400 °C using a gas mixture
containing 10 % C₂H₂ and 90 % H₂ at a total flow rate of 50 mL min⁻¹. Catalyst samples weighing
0.1-0.25 g were used in the experiments.
The rate of hydrogenation product formation was calculated according to equations (1) and (2)
(
1)
(
2)
where, na - the molar fraction of the hydrogenation product in the gas mixture after passing through the
reactor; Vn - the flow rate of the acetylene-hydrogen gas mixture, ml/min, mc - the mass of the catalyst
sample, g; mg - is the mass of reduced graphene oxide (rGO) in the catalyst sample, g.
Каталіз та нафтохімія, 2025, №36 59
Catalysis and Petrochemistry, 2025, 36
Fig. 1. SEM images of the samples: (a) Al2O3; (b) rGO(0.1)/Al2O3; (c) MgO; (d) rGO(0.1)/MgO
Results and Discussion
Fig. 1 a, b shows the SEM images of pristine γ-Al2O3 and the γ-Al2O3 sample modified with
rGO. The surface of the initial γ- Al2O3 is characterized by a porous structure formed by agglomerates of
irregularly shaped nanoparticles [12]. After modification with rGO, film-like formations with a wrinkled
texture, characteristic of graphene layers, appear on the oxide surface [13]. An uneven distribution of the
rGO coating is observed: in some regions, rGO forms continuous films, whereas in others, isolated
graphene folds and exposed areas of the alumina surface remain visible. Such morphology indicates a
non-uniform deposition of rGO and partial coverage of the porous γ-Al2O3 surface.
Fig. 1 c, d presents the SEM images of pristine MgO and the MgO sample modified with reduced
graphene oxide (rGO). The surface of the initial MgO consists of agglomerates of particles with well-
defined cubic facets, typical of this oxide system [14]. After rGO deposition, noticeable changes occur in
the surface morphology: thin film-like structures and folds corresponding to graphene layers appear on
the granular MgO matrix. The rGO is distributed unevenly, forming localized regions with partial
coverage of MgO grains, while some areas remain exposed. The formation of such hybrid regions
60 Каталіз та нафтохімія, 2025, №36
Catalysis and Petrochemistry, 2025, 36
indicates weak interaction between the graphene layers and the MgO surface, which may result in
differences in dispersion and interfacial contact compared to the Al2O3-rGO system.
Fig. 2. FTIR (a) and Raman (b) spectra of rGO (0.0025)/Al₂O₃, rGO (0.01)/Al2O3, rGO (0.1)/Al2O3;
FTIR (c) and Raman (d) spectra of (0.0025)/MgO, rGO (0.01)/MgO, rGO (0.1)/MgO
Fig. 2 a shows the FTIR spectra of pure γ-Al2O3 and the samples modified with different
amounts of reduced graphene oxide. The spectrum of γ- Al2O3 reveals characteristic absorption bands in
the region of 800-500 cm⁻1, corresponding to the stretching and bending vibrations of Al-O and Al-O-Al
bonds [15]. In the high-frequency region 3770-3700 cm⁻1, sharp bands of isolated Al-OH groups are
detected, while a broader feature near 3400 cm⁻1 is attributed to hydrogen-bonded O-H groups and
adsorbed water molecules. After the deposition of reduced graphene oxide, new absorption bands appear
in the spectra. A weak band in the 1730-1710 cm⁻1 region corresponds to the C=O stretching vibrations
of carboxyl groups originating from residual oxygen-containing fragments of graphene oxide [16]. A
distinct band at 1605-1585 cm⁻1 is associated with C=C vibrations of the aromatic structure of graphene
layers. In the region of 1260-1050 cm⁻1, additional bands assigned to C-O-C vibrations of epoxy and
ether groups, as well as C-O vibrations of phenolic groups, are observed. The O-H band in the high-
frequency region becomes broader, suggesting the formation of hydrogen-bonded structures between the
hydroxyl groups of γ-Al₂O₃ and the oxygen functionalities of reduced graphene oxide [17].
Каталіз та нафтохімія, 2025, №36 61
Catalysis and Petrochemistry, 2025, 36
Fig. 2 b shows the FTIR spectra of pure MgO and MgO samples modified with different amounts
of reduced graphene oxide. The spectrum of MgO is characterized by band in the region 500-400 cm⁻1
attributed to lattice vibrations of Mg-O bonds. In the high-frequency region 3740-3700 cm⁻1 a narrow
band assigned to stretching vibrations of isolated Mg-OH groups is observed, while a broader feature
near 3450 cm⁻1 corresponds to hydrogen-bonded O-H groups and adsorbed water on the MgO surface
[23]. After deposition of reduced graphene oxide, additional absorption features appear that are absent in
pure MgO. A band in the region 1720-1700 cm⁻1 is assigned to C=O stretching vibrations of carboxyl
groups originating from residual oxygen-containing fragments of graphene oxide. In the 1605-1585 cm⁻1
region a band characteristic of C=C stretching vibrations of the aromatic framework of graphene layers
is detected, partially overlapping with the H-O-H bending mode of adsorbed water near 1630 cm⁻1 [24].
The presence of paired bands at about 1550 and 1410 cm⁻¹ indicates asymmetric and symmetric
stretching vibrations of carboxylate groups coordinated to magnesium, confirming the formation of
interfacial Mg-carboxylate species [25]. In the mid-frequency region 1260-1220 cm⁻¹ and 1110-1040 cm⁻¹
bands assigned to C-O-C vibrations of epoxy and ether groups and C-O vibrations of phenolic or alkoxy
groups are observed, evidencing the retention of part of the oxygen-containing functionalities and the
formation of Mg-O-C type linkages at the interface [26].
Since the modification of MgO was carried out using an aqueous dispersion of reduced graphene
oxide, the spectra also reveal a broad O-H stretching band in the 3500-3700 cm⁻¹ region together with a
band near 1630 cm⁻¹, characteristic of magnesium hydroxide. These features indicate partial hydration of
surface Mg-O groups with the formation of Mg(OH)2 and the development of a hydroxide-graphene
interfacial layer that promotes effective anchoring of graphene sheets on the MgO surface and stabilizes
the sample structure.
Fig. 2 c, d shows the Raman spectra of the Al2O3- and MgO-based samples modified with
different amounts of reduced graphene oxide (rGO). For all rGO-containing samples, two characteristic
bands of graphene materials – the D band (~ 1350 cm⁻¹) and the G band (~ 1580 cm⁻¹) – are clearly
observed in the 1200-1600 cm⁻¹ region. The ratio of their intensities (I_D/I_G), commonly used as a
measure of defectiveness in carbon materials, exceeds 1 for all compositions and remains essentially
unchanged with increasing rGO loading [18-19]. This indicates that the intrinsic defect level of the
deposited graphene phase stays constant regardless of the amount applied to the oxide surface. An
increase in the absolute intensity of both D and G bands with higher rGO content reflects the growing
concentration of graphene fragments on the supports, while a slight upshift of the G band for Al₂O₃-
based samples may be associated with strain effects within the deposited rGO film [20]. In contrast, the
Raman spectra of the pristine oxide supports do not exhibit graphene-related features: the initial γ-Al₂O₃
shows only low-intensity lattice vibrations in the 300-700 cm⁻¹ region, whereas pure MgO displays weak
Mg-O lattice modes below 800 cm⁻¹ [21-22]. The appearance of D and G bands exclusively after rGO
deposition confirms the successful formation of a graphene-based phase on both oxide supports.
Fig. 3 a shows the temperature dependence of acetylene conversion over rGO/Al₂O₃ catalysts
with different graphene oxide loadings. It should be noted that for both alumina and magnesia deposited
samples in all catalytic experiments, acetylene hydrogenation proceeded to ethylene, maintaining 100 %
selectivity throughout the entire temperature range. No methane or ethane was detected among the
reaction products. The rGO 1 mg/Al2O3 sample exhibits the lowest reaction onset at 150 °C with a
conversion of 6 %, reaching 10 % at 250 °C, and decreasing at higher temperatures to 6 % at 400 °C.
The rGO 0.1 mg/Al₂O₃ catalyst becomes active at 200 °C with a conversion of 0.85 % and shows a
62 Каталіз та нафтохімія, 2025, №36
Catalysis and Petrochemistry, 2025, 36
continuous increase in activity up to 13 % at 400 °C. The rGO 0.025 mg/Al2O3 sample begins to convert
acetylene at about 150 °C with a conversion of 0.4 % and gradually reaches 12 % at 400 °C.
All catalysts exhibit activity within 150-400 °C, with the highest conversion observed for the
rGO 0.1 mg/ Al2O3 sample at 400 °C.
Fig. 3. (a) Temperature dependence of acetylene conversion in the process of acetylene hydrogenation
within the temperature range of 50-400 °C, total flow rate 50 mL min⁻¹; ■ conversion of acetylene on
rGO(0.025)/Al2O3; ● conversion of acetylene on rGO(0.1)/Al2O3; ▲ conversion of acetylene on
rGO(1)/Al2O3. (b) Reaction rate diagrams of acetylene hydrogenation over rGO(0.025)/Al2O3,
rGO(0.1)/Al2O3, and rGO(1)/Al2O3, recalculated per catalyst mass and per rGO mass at 400 °С.
r_c - rate of acetylene hydrogenation normalized to the mass of the catalyst sample; r_g - rate of
acetylene hydrogenation normalized to the mass of rGO in the catalyst sample
The catalyst with the highest rGO content 0.1 mass. % (1 mg/g) shows the lowest initial
temperature for the reaction observed, confirming its superior ability to activate acetylene at low
temperatures. However, the intermediate loading (0.1 mg) provides the best balance between activity
and thermal stability, achieving the highest conversion at 400 °C. These results indicate that an optimal
amount of reduced graphene oxide ensures both efficient low-temperature activation and sustained
catalytic performance under thermal conditions.
Fig. 3 b presents the reaction rate diagrams for acetylene hydrogenation at 400 °C using catalysts
of the rGO/Al2O3system with different contents of reduced graphene oxide. The reaction rate, calculated
per catalyst mass, is 1.8·10⁻⁶ mol·g(cat)⁻¹·s⁻¹ for rGO(0.025)/Al2O3, 2.0·10⁻⁶ mol·g(cat)⁻¹·s⁻¹ for
rGO(0.1)/Al₂O₃, and 8.6·10⁻⁷ mol·g(cat)⁻¹·s⁻¹ for rGO(1)/Al2O3. Thereover, with increasing rGO loading
from 0.0025 mass. % to 0.1 mass. %, the activity first increases – reaching a maximum for the
0.01 mass. % rGO sample – and then decreases. When normalized to the mass of reduced graphene
oxide, the difference becomes more pronounced: 7.04·10⁻² mol·g(rGO)⁻¹·s⁻¹ for rGO(0.025)/Al2O3,
1.96·10⁻² mol·g(rGO)⁻¹·s⁻¹ for rGO(0.1)/Al2O3, and 8.62·10⁻⁴ mol·g(rGO)⁻¹·s⁻¹ for rGO(1)/Al2O3. This
indicates that with increasing rGO content, the specific activity of the catalysts decreases by nearly two
orders of magnitude due to densification or partial coverage of the active surface of the support.
Therefore, the rGO(0.1)/Al2O3 system can be considered optimal, providing the highest reaction rate
(1.96·10⁻⁶ mol·g(cat)⁻¹·s⁻¹) and acetylene conversion of 13 % at 400 °C, demonstrating the effective role
of the graphene layer in reactant activation.
Каталіз та нафтохімія, 2025, №36 63
Catalysis and Petrochemistry, 2025, 36
Fig. 4 a shows the temperature dependence of acetylene conversion over rGO/MgO catalysts
with different graphene oxide loadings. The rGO(0.1)/MgO catalyst becomes active at 250 °C with a
conversion of 1.4 % and gradually increases to 3.8 % at 400 °C.
Fig. 4. (a) Temperature dependence of acetylene conversion in the hydrogenation process within the
temperature range of 50-400 °C, total gas flow rate 50 mL min⁻¹; ■ Acetylene conversion on
rGO(0.0025)/MgO;● Acetylene conversion on rGO(0.01)/MgO; ▲ Acetylene conversion on
rGO(0.1)/MgO. (b) Reaction rate diagrams for acetylene hydrogenation over rGO(0.0025)/MgO,
rGO(0.01)/MgO, and rGO(0.1)/MgO, normalized to the catalyst mass and to the mass of rGO.
rₛ - rate of acetylene hydrogenation normalized to the catalyst mass;
r₉ - rate of acetylene hydrogenation normalized to the mass of rGO in the catalyst sample
The rGO(0.01)/MgO sample starts to convert acetylene at 300 °C with a conversion of 1.2 % and
reaches 3.7 % at 400 °C. The rGO(0.0025)/MgO catalyst shows activity from 250 °C with a conversion
of 0.9 % and steadily increases to 4.8 % at 400 °C. All rGO/MgO catalysts remain active within
250-400 °C, with the highest conversion observed for the rGO(0.025)/MgO sample at 400 °C. The
highest conversion 4.8 % at 400 °C, is achieved for rGO(0.0025)/MgO, indicating that smaller graphene
loadings favor better dispersion and stronger interfacial contact with the MgO support. Compared to the
rGO/Al2O3system, the MgO-based catalysts demonstrate lower activity but maintain stable performance
over the examined temperature interval.
Fig. 4 b shows the reaction rate diagrams for acetylene hydrogenation at 400 °C over rGO/ MgO
catalysts with different loadings of reduced graphene oxide. The reaction rate, calculated per catalyst
mass, is 7.20·10⁻⁷ mol·g(cat)⁻¹·s⁻¹ for rGO(0.0025)/MgO, 5.43·10⁻⁷ mol·g(cat)⁻¹·s⁻¹ for rGO(0.01)/MgO,
and 1.42·10⁻⁶ mol·g(cat)⁻¹·s⁻¹ for rGO(0.1)/MgO. At low rGO contents (0.0025-0.1 mg/g), the catalytic
activity remains relatively low, whereas increasing the rGO loading to 1 wt. % leads to nearly a twofold
increase in the reaction rate, which can be attributed to the formation of a more continuous graphene
coating and improved interfacial contact between MgO and the rGO layer. When normalized to the mass
of reduced graphene oxide, the rate values are 2.88·10⁻² mol·g(rGO)⁻¹·s⁻¹ for rGO(0.0025)/MgO,
5.43·10⁻³ mol·g(rGO)⁻¹·s⁻¹ for rGO(0.01)/MgO, and 1.42·10⁻³ mol·g(rGO)⁻¹·s⁻¹ for rGO(0.1)/MgO. The
observed decrease in specific activity with increasing rGO content may result from partial shielding of
active centers by graphene layers or from the formation of Mg(OH)₂ during the deposition of rGO from
an aqueous suspension.
Therefore, for the rGO/MgO, the highest acetylene hydrogenation rate based on catalyst mass is
observed at 400 °C for rGO(0.1)/MgO - 1.42·10⁻⁶ mol·g(cat)⁻¹·s⁻¹, although its acetylene conversion
64 Каталіз та нафтохімія, 2025, №36
Catalysis and Petrochemistry, 2025, 36
reaches only 4 %. This suggests partial coverage of the active MgO surface or diffusion limitations of
reactants within the graphene layer. Meanwhile, the specific activity normalized to the rGO mass for all
rGO/MgO samples remains lower than that of analogous γ- Al2O3-based systems.
The experiments show that both rGO/Al₂O₃ and rGO/MgO catalysts are active in acetylene
hydrogenation, although their temperature-dependent behavior and efficiency differ noticeably. The
rGO/Al2O3 samples demonstrate higher conversions across the studied temperature range and begin to
exhibit measurable activity at lower temperatures. This suggests that γ-Al2O3 provides surface conditions
more favorable for the surface reaction between adsorbed acetylene and hydrogen [27]. It can be
proposed that the presence of surface hydroxyl groups on alumina facilitates stronger interaction
between the deposited rGO layers and the oxide surface, providing new or enhancing existing active
sites [28].
In contrast, the rGO/MgO catalysts show lower acetylene conversion and require higher
temperatures to reach comparable activity trends. The predominantly basic character of MgO results in
weaker interaction with the graphene phase, which can be conditioned by interaction between carboxylic
groups in OG and MgO due to the first step of deposition [29]. In addition, partial hydration of the MgO
surface during deposition from an aqueous rGO suspension leads to the formation of Mg(OH)2, and
interaction of MgO with atmospheric CO2 can significantly reduce the surface hydrogen migration due
to poisoning of the surface by blocking -OH groups [30]. This modification of the surface composition
limits hydrogen surface mobility and contributes to lower overall activity. Nevertheless, all MgO-based
catalysts retain stable operation throughout the reaction temperature range.
Across both systems, the amount of deposited reduced graphene oxide is a key factor in
determining catalytic behaviour. Lower rGO loadings ensure better dispersion and a more open surface,
whereas higher loadings may lead to partial coverage of the oxide grains and restricted access to active
regions. This effect is more pronounced for MgO, where thicker graphene layers can hinder contact
between reactants and the basic surface sites [31-32]. In the Al2O3-supported samples, moderate rGO
loadings improve catalytic performance while preserving the structural accessibility of the support.
Conclusions
Therefore, the obtained results show that the optimal content of reduced graphene oxide lies in
the range of 0.025-0.1 mg, which provides a balance between low-temperature activity and thermal
stability of the catalytic system. Among the investigated samples, the rGO 0.1 mg/Al2O3 catalyst
provides the highest acetylene conversion of 13 % at 400 °C, with 100 % selectivity to ethylene and
stable performance throughout the reaction. Overall, the observed trends indicate that the catalytic
behavior of graphene-oxide catalysts is mainly determined by the acid-base properties of the support and
the structural characteristics of the rGO layer, which together influence both the temperature required for
activation and the thermal stability of the system. The results obtained may serve as a basis for the
rational design of metal-free or low-metal hydrogenation catalysts for selective transformations of
unsaturated hydrocarbons.
References
1. Studt F., Calle-Vallejo F., Luo J., Hansen H.A., Nørskov J.K., Bligaard T. On the role of surface structure for
catalyst selectivity by first-principles theory. ChemCatChem, 2012, 4(11), 1809–1815.
2. Borodziński A., Bond G.C. Selective hydrogenation of ethyne in ethene-rich streams on palladium catalysts.
Part 1: Oxide supports. Catal. Rev., 2006, 48(1), 91–144.
Каталіз та нафтохімія, 2025, №36 65
Catalysis and Petrochemistry, 2025, 36
3. Liu Y., Wang Z., Zhang X. Review on graphene-based metal-free catalysts: Synthesis and applications.
Chem. Eng. J., 2015, 270, 1–25.
4. Chen X., Park J., Ruoff R.S. Chemical functionalization of graphene and its applications. Chem. Rev., 2016,
116(14), 704–711.
5. Dreyer D.R., Park S., Bielawski C.W., Ruoff R.S. The chemistry of graphene oxide. Chem. Soc. Rev., 2010,
39(1), 228–240.
6. Loh K.P., Bao Q., Eda G., Chhowalla M. Graphene oxide as a chemically tunable platform for optical
applications. Nat. Chem., 2010, 2(12), 1015–1024.
7. Stankovich S., Dikin D.A., Piner R.D., et al. Synthesis of graphene-based nanosheets via chemical reduction
of exfoliated graphite oxide. Carbon, 2007, 45(7), 1558–1565.
8. Abakumov A., Bychko I.B., Selyshchev O.V., Zahn D.R.T., Qi X., Tang J., Stryzhak P.Ye. Highly selective
hydrogenation of acetylene over reduced graphene oxide carbocatalyst. Materialia, 2021, 18, 101163.
9. Zhu C., Sheng J., Lu R. Metal-free hydrogenation of alkynes using nitrogen-doped graphene as a catalyst.
ACS Catal., 2018, 8(10), 10081–10088.
10. Primo A., Neatu F., Florea M., Parvulescu V., Garcia H. Graphenes in the absence of metals as carbocatalysts
for selective acetylene hydrogenation and alkene hydrogenation. Nat. Commun., 2014, 5, 5291.
11. Nosach V.V., Bychko I.B., Stryzhak P.Ye. Catalytic properties of reduced graphene oxide deposited on
aluminum oxide in ethane dehydrogenation. Theor. Exp. Chem., 2025, 61(2), 121–126. [in Ukranian].
12. Kheirandish E., Taherzadeh M. Quasi-2D crystalline γ-alumina grown by graphene-templated method. Adv.
Mater. Interfaces, 2020, 7(3), 2000561.
13. Gómez-Navarro C., Burghard M., Kern K. Atomic structure of reduced graphene oxide. Nano Lett., 2010,
10(4), 1144–1148.
14. Long Y., Zhang Z., Zhao X., Wang D. Field emission of MgO-coated graphene sheets prepared by atomic
layer deposition. J. Vac. Sci. Technol. B, 2015, 33(1), 012204.
15. Busca G. Acid-base properties of metal oxide surfaces and their characterization by IR spectroscopic
methods. Adv. Catal., 2014, 57, 319–404.
16. Navalon S., Dhakshinamoorthy A., Alvaro M., García H. Carbocatalysis by graphene-based materials. Chem.
Rev., 2014, 114(12), 6179–6212.
17. Acik M., Lee G., Mattevi C., Chhowalla M., Cho K., Chabal Y.J. Unusual infrared-absorption mechanism in
thermally reduced graphene oxide. Nat. Mater., 2010, 9(10), 840–845.
18. Ferrari A.C. Raman spectroscopy of graphene and graphite: Disorder, electron-phonon coupling, doping and
nonadiabatic effects. Solid State Commun., 2007, 143(1–2), 47–57.
19. Eckmann A., Felten A., Mishchenko A., Britnell L., Krupke R., Novoselov K.S., Casiraghi C. Probing the
nature of defects in graphene by Raman spectroscopy. Nano Lett., 2012, 12(8), 3925–3930.
20. Mohiuddin T.M.G., Lombardo A., Nair R.R., Bonetti A., Savini G., Jalil R., Ferrari A.C. Uniaxial strain in
graphene by Raman spectroscopy. Phys. Rev. B, 2009, 79(20), 205433.
21. Busca G. The surface of transitional aluminas: A critical review. Catal. Today, 2014, 226, 2–13.
22. Gotić M., Ivanda M., Sekulić A., Musić S., Matthews A., Popović S. Raman spectroscopic study of MgO and
Mg(OH)₂ under high pressure. J. Mol. Struct., 2000, 555(1–3), 353–360.
23. Frost R.L., Kloprogge J.T. Vibrational spectroscopy of hydroxyl groups in MgO-H₂O system. Spectrochim.
Acta A, 1999, 55(12), 2195–2205.
24. Liu P., Yan Y. Preparation and characterization of reduced graphene oxide and its composite with TiO₂ by
FTIR and Raman spectroscopy. Appl. Surf. Sci., 2010, 256(9), 2810–2814.
25. Reddy B.M., Khan A. Promoted MgO catalysts for organic transformations: FTIR characterization of
carbonate and carboxylate species on MgO. J. Mol. Catal. A, 2005, 230(1–2), 33–39.
26. Hu Y., Shen J., Li N., Ma H., Shi M., Ye M. Microwave-assisted reduction and functionalization of graphene
oxide on MgO surfaces. J. Phys. Chem. C, 2010, 114(20), 9308–9313.
66 Каталіз та нафтохімія, 2025, №36
Catalysis and Petrochemistry, 2025, 36
27. Gao J., Chen S., Wang H. Effect of support acidity on catalytic performance of Pt-based catalysts for
selective hydrogenation of acetylene. Catal. Today, 2017, 295, 110–118.
28. Santos A.L.R., et al. Quantification of hydroxyl groups on alumina supports and their role in catalytic
activity. Braz. J. Anal. Chem., 2018, 5(20), 48–59.
29. Kwon O., Park J., Kim J., Song I. Acid-base properties of metal oxides and their influence on catalytic
hydrogenation reactions. J. Mol. Catal. A, 2015, 398, 156–164.
30. Busca G. Bases and basic materials in heterogeneous catalysis: MgO, CaO, hydrotalcites and related
materials. Catal. Today, 2009, 143, 2–8.
31. Torshizi H.O., Nakhaei Pour A., Mohammadi A., Zamani Y., Shahri S.M.K., Kamali Shahri S.M. Fischer-
Tropsch synthesis by reduced graphene oxide nanosheets supported cobalt catalysts. Front. Chem. Sci. Eng.,
2021, 15, 299–309.
32. Grigoriev S.A., et al. Reduced graphene oxide (RGO) and its modifications as catalyst supports: Effects of
loading and layer thickness. Materials, 2018, 11(8), 1405.
Надійшла до редакції 20.11.2025
Каталітичні властивості відновленого оксиду графену, нанесеного на оксиди
алюмінію та магнію, у реакції гідрування ацетилену
Вікторія В. Носач 1, 2, Ігор Б. Бичко 1, Петро Є. Стрижак 1
¹ Інститут фізичної хімії ім. Л.В. Писаржевського Національної академії наук України
просп. Науки, 31, Київ, 03028, Україна
² Національний університет «Києво-Могилянська академія»
вул. Григорія Сковороди, 2, Київ, 04655, Україна, е-mail: victorynosach@gmail.com
Каталітичні властивості відновленого оксиду графену (ВОГ), нанесеного на оксиди алюмінію та
магнію, були досліджені в реакції гідрування ацетилену. Каталізатори з різним вмістом ВОГ отримували
методом просочення γ-Al₂O₃ та MgO водними суспензіями оксиду графену з подальшим відновленням у
водні за 400 °C. Матеріали характеризували за допомогою Фур’є-ІЧ спектроскопії (ІЧ), Раманівської
спектроскопії та СЕМ. ІЧ-спектри підтвердили успішне нанесення rGO на обидві підкладки, а для зразків
на основі MgO також виявили часткову гідратацію поверхневих Mg–O груп з утворенням Mg(OH)₂ та
гідроксидно-графенового міжфазного шару, який покращує закріплення та стабілізує структуру. За
допомогою Раманівської спектроскопії було підтверджено формування графенвмісної фази на обох
оксидах і показано, що рівень дефектності осадженого графену залишається постійним при зміні вмісту
ВОГ. Аналіз зображень СЕМ виявив, що на ВОГ/MgO утворює тонкі плівкоподібні структури та
нерегулярні складки, які формують частково покриті ділянки, тоді як на γ-Al₂O₃ він утворює безперервні
плівки в одних зонах і ізольовані складки в інших. Модифікація γ-Al₂O₃ та MgO відновленим оксидом
графену підвищила каталітичну активність зразківу гідруванні ацетилену, причому найвищі швидкості
спостерігалися для зразків із низьким вмістом ВОГ. Обидва каталізатори – ВОГ/Al₂O₃ та ВОГ/MgO –
продемонстрували повну (100 %) селективність за етиленом в діапазоні 250-400 °C. Підвищення
активності пояснюється наявністю поверхневих структур, утворених ВОГ, які забезпечують ефективний
контакт між вуглецевою та оксидною фазами й сприяють активації ацетилену та водню. Загалом
каталітична активність оксидів, модифікованих ВОГ, визначається кислотно-основними властивостями
носія та структурними особливостями нанесеного графенового шару, які задають температуру активації та
термічну стабільність системи.
Ключові слова: відновлений оксид графену, оксид алюмінію, оксид магнію, гідрування ацетилену,
каталіз
|
| id | oai:katalizorgua:article-128 |
| institution | Catalysis and petrochemistry |
| keywords_txt_mv | keywords |
| language | English |
| last_indexed | 2026-03-12T15:50:23Z |
| publishDate | 2025 |
| publisher | V.P. Kukhar Institute of Bioorganic Chemistry and Petrochemistry of the National Academy of Sciences of Ukraine |
| record_format | ojs |
| resource_txt_mv | katalizorgua/c9/a4125a07dcf3857e1572e053fc8c3ec9.pdf |
| spelling | oai:katalizorgua:article-1282025-12-28T17:23:30Z Catalytic properties of reduced graphene oxide deposited on aluminum and magnesium oxides in acetylene hydrogenation Catalytic properties of reduced graphene oxide deposited on aluminum and magnesium oxides in acetylene hydrogenation Nosach, Viktoriia V. Bychko, Igor B. Strizhak , Peter Ye. reduced graphene oxide, aluminum oxide, magnesium oxide, acetylene hydrogenation, carbocatalysis відновлений оксид графену, оксид алюмінію, оксид магнію, гідрування ацетилену, каталіз The catalytic properties of reduced graphene oxide (rGO) deposited on aluminum and magnesium oxides were investigated in acetylene hydrogenation. Catalysts with different rGO loadings were prepared by impregnating γ-Al₂O₃ and MgO with aqueous graphene oxide suspensions, followed by reduction in hydrogen at 400 °C. The materials were characterized by FTIR, Raman spectroscopy, and SEM. FTIR spectra confirmed the successful deposition of rGO on both supports, and for MgO-based samples, FTIR also revealed partial hydration of surface Mg–O groups, forming Mg(OH)₂ and a hydroxide–graphene interfacial layer that improves anchoring and stabilizes the structure. Raman spectroscopy verified the formation of a graphene-based phase on both oxides and showed that the defect level of the deposited graphene remains constant with varying rGO loading. SEM analysis indicated that on MgO, rGO forms thin film-like structures and irregular folds that create partially covered regions, while on γ-Al₂O₃ it forms continuous films in some areas and isolated folds in others. Modification of γ-Al₂O₃ and MgO with rGO enhanced catalytic activity in acetylene hydrogenation, with the highest rates observed for samples with low rGO content. Both rGO/Al₂O₃ and rGO/MgO exhibited full (100 %) selectivity to ethylene in the 250–400 °C range. The improved performance is attributed to rGO-derived surface structures that ensure effective contact between carbon and oxide phases and facilitate activation of acetylene and hydrogen. Overall, the catalytic behavior of rGO-modified oxides is governed by the acid–base properties of the support and the structural features of the deposited graphene layer, which determine the activation temperature and thermal stability of the system. Каталітичні властивості відновленого оксиду графену (ВОГ), нанесеного на оксиди алюмінію та магнію, були досліджені в реакції гідрування ацетилену. Каталізатори з різним вмістом ВОГ отримували методом просочення γ-Al₂O₃ та MgO водними суспензіями оксиду графену з подальшим відновленням у водні за 400 °C. Матеріали характеризували за допомогою Фур’є-ІЧ спектроскопії (ІЧ), Раманівської спектроскопії та СЕМ. ІЧ-спектри підтвердили успішне нанесення rGO на обидві підкладки, а для зразків на основі MgO також виявили часткову гідратацію поверхневих Mg–O груп з утворенням Mg(OH)₂ та гідроксидно-графенового міжфазного шару, який покращує закріплення та стабілізує структуру. За допомогою Раманівської спектроскопії було підтверджено формування графенвмісної фази на обох оксидах і показано, що рівень дефектності осадженого графену залишається постійним при зміні вмісту ВОГ. Аналіз зображень СЕМ виявив, що на ВОГ/MgO утворює тонкі плівкоподібні структури та нерегулярні складки, які формують частково покриті ділянки, тоді як на γ-Al₂O₃ він утворює безперервні плівки в одних зонах і ізольовані складки в інших. Модифікація γ-Al₂O₃ та MgO відновленим оксидом графену підвищила каталітичну активність зразківу гідруванні ацетилену, причому найвищі швидкості спостерігалися для зразків із низьким вмістом ВОГ. Обидва каталізатори – ВОГ/Al₂O₃ та ВОГ/MgO – продемонстрували повну (100 %) селективність за етиленом в діапазоні 250-400 °C. Підвищення активності пояснюється наявністю поверхневих структур, утворених ВОГ, які забезпечують ефективний контакт між вуглецевою та оксидною фазами й сприяють активації ацетилену та водню. Загалом каталітична активність оксидів, модифікованих ВОГ, визначається кислотно-основними властивостями носія та структурними особливостями нанесеного графенового шару, які задають температуру активації та термічну стабільність системи. V.P. Kukhar Institute of Bioorganic Chemistry and Petrochemistry of the National Academy of Sciences of Ukraine 2025-12-08 Article Article application/pdf https://kataliz.org.ua/index.php/journal/article/view/128 10.15407/kataliz2025.36.057 Catalysis and petrochemistry; No. 36 (2025): Catalysis and petrochemistry; 57-66 Каталіз та нафтохімія; № 36 (2025): Каталіз та нафтохімія; 57-66 2707-5796 2412-4176 10.15407/kataliz2025.36 en https://kataliz.org.ua/index.php/journal/article/view/128/112 Copyright (c) 2025 Catalysis and petrochemistry |
| spellingShingle | відновлений оксид графену оксид алюмінію оксид магнію гідрування ацетилену каталіз Nosach, Viktoriia V. Bychko, Igor B. Strizhak , Peter Ye. Catalytic properties of reduced graphene oxide deposited on aluminum and magnesium oxides in acetylene hydrogenation |
| title | Catalytic properties of reduced graphene oxide deposited on aluminum and magnesium oxides in acetylene hydrogenation |
| title_alt | Catalytic properties of reduced graphene oxide deposited on aluminum and magnesium oxides in acetylene hydrogenation |
| title_full | Catalytic properties of reduced graphene oxide deposited on aluminum and magnesium oxides in acetylene hydrogenation |
| title_fullStr | Catalytic properties of reduced graphene oxide deposited on aluminum and magnesium oxides in acetylene hydrogenation |
| title_full_unstemmed | Catalytic properties of reduced graphene oxide deposited on aluminum and magnesium oxides in acetylene hydrogenation |
| title_short | Catalytic properties of reduced graphene oxide deposited on aluminum and magnesium oxides in acetylene hydrogenation |
| title_sort | catalytic properties of reduced graphene oxide deposited on aluminum and magnesium oxides in acetylene hydrogenation |
| topic | відновлений оксид графену оксид алюмінію оксид магнію гідрування ацетилену каталіз |
| topic_facet | reduced graphene oxide aluminum oxide magnesium oxide acetylene hydrogenation carbocatalysis відновлений оксид графену оксид алюмінію оксид магнію гідрування ацетилену каталіз |
| url | https://kataliz.org.ua/index.php/journal/article/view/128 |
| work_keys_str_mv | AT nosachviktoriiav catalyticpropertiesofreducedgrapheneoxidedepositedonaluminumandmagnesiumoxidesinacetylenehydrogenation AT bychkoigorb catalyticpropertiesofreducedgrapheneoxidedepositedonaluminumandmagnesiumoxidesinacetylenehydrogenation AT strizhakpeterye catalyticpropertiesofreducedgrapheneoxidedepositedonaluminumandmagnesiumoxidesinacetylenehydrogenation |