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1.
Gels ; 10(3)2024 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-38534583

RESUMO

Agar, a naturally occurring polysaccharide, has been modified by grafting it with acrylic (AcA) and methacrylic (McA) acid monomers, resulting in acrylic or methacrylic acid grafted polymer (AA-g-AcA or AA-g-McA) with pH-sensitive swelling behavior. Different ratios between agar, monomers, and initiator were applied. The synthesized grades of both new polymer series were characterized using FTIR spectroscopy, NMR, TGA, DSC, and XRD to ascertain the intended grafting. The percentage of grafting (% G), grafting efficiency (% GE), and % conversion (% C) were calculated, and models with optimal characteristics were further characterized. The swelling behavior of the newly synthesized polymers was studied over time and in solutions with different pH. These polymers were subsequently crosslinked with varying amounts of glutaraldehyde to obtain 5-fluorouracil-loaded nanogels. The optimal ratios of polymer, drug, and crosslinker resulted in nearly 80% loading efficiency. The performed physicochemical characterization (TEM and DLS) showed spherical nanogels with nanometer sizes (105.7-250 nm), negative zeta potentials, and narrow size distributions. According to FTIR analysis, 5-fluorouracil was physically incorporated. The swelling and release behavior of the prepared nanogels was pH-sensitive, favoring the delivery of the chemotherapeutic to tumor cells. The biocompatibility of the proposed nanocarrier was proven using an in vitro hemolysis assay.

2.
Pharmaceuticals (Basel) ; 17(2)2024 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-38399401

RESUMO

In this study, doxorubicin was loaded in a chitosan-albumin nanogel with the aim of improving its stability and exploring the potential of the system in the treatment of skin cancer. Infrared spectroscopy and X-ray diffraction confirmed the encapsulation of the drug. Transmission electron microscopy revealed the spherical shape of the nanogel particles. The drug-loaded nanogel was characterized with a small diameter of 29 nm, narrow polydispersity (0.223) and positive zeta potential (+34 mV). The exposure of encapsulated doxorubicin to light (including UV irradiation and daylight) did not provoke any degradation, whereas the nonencapsulated drug was significantly degraded. In vitro studies on keratinocytes (HaCaT) and epidermoid squamous skin carcinoma cells (A-431) disclosed that the encapsulated doxorubicin was more cytotoxic on both cell lines than the pure drug was. More importantly, the cytotoxic concentration of encapsulated doxorubicin in carcinoma cells was approximately two times lower than that in keratinocytes, indicating that it would not affect them. Thus, the loading of doxorubicin into the developed chitosan-albumin nanogel definitely stabilized the drug against photodegradation and increased its antineoplastic effect on the skin cancer cell line.

3.
Gels ; 10(1)2024 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-38275852

RESUMO

Budesonide is a mineral corticoid applied in the local therapy of pediatric atopic dermatitis. Unfortunately, its dermal administration is hindered by the concomitant adverse effects and its physicochemical properties. The characteristic pH change in the atopic lesions can be utilized for the preparation of a pH-sensitive nanocarrier. In this view, the formulation of Eudragit L 100 nanoparticles as a budesonide delivery platform could provide more efficient release to the desired site, improve its penetration, and subsequently lower the undesired effects. In this study, budesonide-loaded Eudragit L100 nanoparticles were prepared via the nanoprecipitation method (mean diameter 57 nm, -31.2 mV, and approx. 90% encapsulation efficiency). Their safety was proven by cytotoxicity assays on the HaCaT keratinocyte cell line. Further, the drug-loaded nanoparticles were incorporated into two types of hydrogels based on methylcellulose or Pluronic F127. The formulated hydrogels were characterized with respect to their pH, occlusion, rheology, penetration, spreadability, and drug release. In conclusion, the developed hydrogels containing budesonide-loaded nanoparticles showed promising potential for the pediatric treatment of atopic dermatitis.

4.
Materials (Basel) ; 16(19)2023 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-37834684

RESUMO

The magneto-optical (MO) Kerr effects for ZnO and ZnO:Ni-doped nanolaminate structures prepared using atomic layer deposition (ALD) have been investigated. The chemical composition and corresponding structural and morphological properties were studied using XRD and XPS and compared for both nanostructures. The 2D array gradient maps of microscale variations of the Kerr angle polarization rotation were acquired by means of MO Kerr microscopy. The obtained data revealed complex behavior and broad statistical dispersion and showed distinct qualitative and quantitative differences between the undoped ZnO and ZnO:Ni-doped nanolaminates. The detected magneto-optical response is extensively inhomogeneous in ZnO:Ni films, and a giant Kerr polarization rotation angle reaching up to ~2° was established. This marks the prospects for further development of magneto-optical effects in ALD ZnO modified by transition metal oxide nanostructures.

5.
Materials (Basel) ; 16(20)2023 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-37895608

RESUMO

Bacterial infection is one of the most common and harmful medical issues following the implantation of materials and devices in the body leading to antibiotic resistance of diverse bacterial strains. In this work, a novel approach is presented combining adopted laser-based patterning method in addition to doping (Mg and Zn) metal ions to prepare calcium phosphate ceramic substrate, applicable in medicine, with enhanced surface antimicrobial characteristics. The preparation of tablets containing Mg (8.44 mol%) and Zn (2.63 mol%) ß-tricalcium phosphate involved biomimetic precipitation of amorphous calcium phosphate in media of simulated body fluid enriched with Mg2+ and Zn2+ ions as well as the presence of valine as an organic additive, followed by step-wise calcination up to 1000 °C. The results from laser processing showed formation of deeper patterns with increased surface roughness (from 4.9 µm to 9.4 µm) as laser power and velocity increase, keeping constant the hatch sizes of 50 µm. The textured surfaces consist of peaks and valleys arrangement that change the morphology of Escherichia coli cells and decrease of cell viability. Our study reveals the possibilities of the application of ultra-short laser radiation as a potential alternative therapy for controlling the antimicrobial effect of the ceramic surface.

6.
Materials (Basel) ; 16(20)2023 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-37895620

RESUMO

The preparation of specially doped calcium phosphates (CaPs) is receiving a great deal of attention from researchers due to CaPs' enhanced capabilities for application in medicine. Complexation and precipitation in a complicated electrolyte system including simulated body fluids that are enriched with Mg2+ and Zn2+ ions and modified with glycine, alanine and valine were first evaluated using a thermodynamic equilibrium model. The influence of the type and concentration of amino acid on the incorporation degree of Mg and Zn into the solid phases was predicted. Experimental studies, designed on the basis of thermodynamic calculations, confirmed the predictions. Amorphous calcium phosphates double-doped with Mg and Zn were biomimetically precipitated and transformed into Mg, Zn-ß-tricalcium phosphates (TCP) upon calcination. The Rietveld refinement confirmed that Mg2+ and Zn2+ substituted Ca2+ only at the octahedral sites of ß-TCP, and in some cases, fully displacing the Ca2+ from them. The resulting Mg, Zn-ß-TCP can serve as a reservoir for Mg and Zn ions when included in the formulation of a biomaterial for bone remodeling. The research conducted reveals the effect of combining mathematical models with experimental studies to pre-evaluate the influence of various additives in the design of materials with predetermined properties.

7.
Materials (Basel) ; 16(20)2023 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-37895766

RESUMO

New results on the effect of TiO2 on Pd/La2O3-CeO2-Al2O3 systems for catalytic oxidation of methane in the presence of H2O and SO2 have been received. Low-temperature N2-adsorption, XRD, SEM, HRTEM, XPS, EPR and FTIR techniques were used to characterize the catalyst. The presence of Ce3+ on the catalytic surface and in the volume near the lantana was revealed by EPR and XPS. After aging, the following changes are observed: (i) agglomeration of the Pd-clusters (from 8 nm to 12 nm); (ii) transformation of part of the TiO2 from anatase to larger particles of rutile; and (iii)-the increase in PdO/Pd-ratio above its optimum. The modification by Ti of the La2O3-CeO2-Al2O3 system leads to higher resistance towards the presence of SO2 most likely due to the prevailing formation of unstable surface sulfites instead of thermally stable sulfates. Based on kinetic model calculations, the reaction pathway over the Pd/La2O3-CeO2-TiO2-Al2O3 catalyst follows the Mars-van Krevelen mechanism. For evaluation of the possible practical application of the obtained material, a sample of Pd/La2O3-CeO2-TiO2-Al2O3, supported on rolled aluminum-containing stainless steel (Aluchrom VDM®), was prepared and tested. Methane oxidation in an industrial-scale monolithic reactor was simulated using a two-dimensional heterogeneous reactor model.

8.
Gels ; 9(9)2023 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-37754450

RESUMO

Hydrogels can offer many opportunities for drug delivery strategies. They can be used on their own, or their benefits can be further exploited in combination with other nanocarriers. Intelligent hydrogels that react to changes in the surrounding environment can be utilized as gatekeepers and provide sustained on-demand drug release. In this study, a hybrid nanosystem for temperature- and pH-sensitive delivery was prepared from MCM-41 nanoparticles grafted with a newly synthesized thermosensitive hydrogel (MCM-41/AA-g-PnVCL). The initial particles were chemically modified by the attachment of carboxyl groups. Later, they were grafted with agar (AA) and vinylcaprolactam (VCL) by free radical polymerization. Doxorubicin was applied as a model hydrophilic chemotherapeutic drug. The successful formulation was confirmed by FT-IR and TGA. Transmission electron microscopy and dynamic light scattering analysis showed small particles with negative zeta potential. Their release behaviour was investigated in vitro in media with different pH and at different temperatures. Under tumour simulating conditions (40 °C and pH 4.0), doxorubicin was almost completely released within 72 h. The biocompatibility of the proposed nanoparticles was demonstrated by in vitro haemolysis assay. These results suggest the possible parenteral application of the newly prepared hydrogel-functionalized mesoporous silica nanoparticles for temperature-sensitive and pH-triggered drug delivery at the tumour site.

9.
Nanomaterials (Basel) ; 13(17)2023 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-37686936

RESUMO

High surface-area, mesoporous CeO2, ZrO2, and Ce-Zr composite nanoparticles were developed using the hydrothermal template-assisted synthesis method. Samples were characterized using XRD, N2 physisorption, TEM, XPS, and FT-IR spectroscopic methods. The CO2 adsorption ability of the obtained materials was tested under dynamic and equilibrium conditions. A high CO2 adsorption capacity in CO2/N2 flow or CO2/N2/H2O was determined for all studied adsorbents depending on their composition flow. A higher CO2 adsorption was registered for Ce-Zr composite nanomaterials due to the presence of strong O2- base sites and enriched surface oxygen species. The role of the Ce/Zr ratio is the process of the formation of highly active and selective adsorption sites is discussed. The calculated heat of adsorption revealed the processes of chemisorption and physisorption. Experimental data could be appropriately described by the Yoon-Nelson kinetic model. The composites reused in five adsorption/desorption cycles showed a high stability with a slight decrease in CO2 adsorption capacities in dry flow and in the presence of water vapor.

10.
Materials (Basel) ; 16(17)2023 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-37687447

RESUMO

In the current investigation, the removal efficiency regarding a cationic dye, methylene blue (MB), from three graphene-based materials was investigated. The materials' characterization process involved instrumental methods such as XRD, XPS, SEM, TEM, FTIR, and nitrogen adsorption at 77 K. The survey examined how various process factors influenced the ability of the studied materials to adsorb cationic dyes. These parameters encompassed contact time, initial dye concentrations, solution pH, and temperature. The adsorption procedure was effectively explained through the application of pseudo-second-order and Langmuir models. The maximum adsorption capacity for the best adsorbent at 293 K was found to be 49.4 mg g-1. In addition, the study also determined the entropy, enthalpy, and Gibbs free energy values associated with the removal of MB and showed that the adsorption of MB is endothermic, feasible, and spontaneous. The results also revealed that the studied materials are suitable adsorbents for the removal of cationic dyes.

11.
Materials (Basel) ; 16(18)2023 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-37763486

RESUMO

Open-cell AMMCs are high-strength and lightweight materials with applications in different types of industries. However, one of the main goals in using these materials is to enhance their tribological behavior, which improves their durability and performance under frictional conditions. This study presents an approach for fabricating and predicting the wear behavior of open-cell AlSn6Cu-SiC composites, which are a type of porous AMMCs with improved tribological properties. The composites were fabricated using liquid-state processing, and their tribological properties are investigated by the pin-on-disk method under different loads (50 N and 100 N) and with dry-sliding friction. The microstructure and phase composition of the composites were investigated by scanning electron microscopy, energy-dispersive X-ray spectroscopy, and X-ray diffraction. The mass wear and coefficient of friction (COF) of the materials were measured as quantitative indicators of their tribological behavior. The results showed that the open-cell AlSn6Cu-SiC composite had an enhanced tribological behavior compared to the open-cell AlSn6Cu material in terms of mass wear (38% decrease at 50 N and 31% decrease at 100 N) while maintaining the COF at the same level. The COF of the composites was predicted by six different machine learning methods based on the experimental data. The performance of these models was evaluated by various metrics (R2, MSE, RMSE, and MAE) on the validation and test sets. Based on the results, the open-cell AlSn6Cu-SiC composite outperformed the open-cell AlSn6Cu material in terms of mass loss under different loads with similar COF values. The ML models that were used can predict the COF accurately and reliably based on features, but they are affected by data quality and quantity, overfitting or underfitting, and load change.

12.
Materials (Basel) ; 16(15)2023 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-37570149

RESUMO

The effect of copper as a minority alloying element on the corrosion behaviour of amorphous and crystalline Al74Ni16Si10 and Al74Ni15Si9Cu2 alloys was investigated in this study. Amorphous alloys were produced as rapidly solidified ribbons using the Chill Block Melt Spinning (CBMS) method and subsequently annealed to complete crystallisation. The corrosion rate of alloys was obtained through continuous immersion tests in 3.5% NaCl at 25 °C and 50 °C for 360 h. The electrochemical parameters corrosion current density (Jcorr) and corrosion potential (Ecorr) were determined via the potentiodynamic polarisation test. The results showed better corrosion characteristics of amorphous alloys. The addition of 2 at.% copper to the Al74Ni16Si10 alloy improved pitting corrosion resistance without significant effect on the corrosion current and potential. In immersion tests at 25 °C, the presence of copper resulted in an increase in the corrosion rate of about 300% for both amorphous and crystalline alloys. At a temperature of 50 °C, this increase is on average 130%. The apparent difference between the results of the two test methods is discussed in terms of the imperfections on the surface of rapidly solidified ribbons. The results of this study will contribute to a more complex understanding of the nature of amorphous alloys and their application.

13.
Bioengineering (Basel) ; 10(6)2023 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-37370568

RESUMO

BACKGROUND: One of the therapeutic limitations of the use of doxorubicin (DOX) as an anticancer drug is its cardiotoxicity. Its hydrophilicity also causes difficulties in achieving sustained release. The simultaneous delivery with the well-known natural antioxidant quercetin could ameliorate its cardiotoxicity. Thus, the main aim of this work is to study the potential of carboxylated and non-carboxylated mesoporous silica MCM-41 nanoparticles for double loading of the hydrophilic doxorubicin hydrochloride and hydrophobic quercetin (Q) in one nanocarrier with a modified release pattern to reduce the cardiotoxic side effects of doxorubicin in vitro. METHODS: The methods included the modification of MCM-41, single and double loading of modified and non-modified MCM-41, physicochemical characterization, in vitro release tests and kinetic study, and in vitro cell viability studies. RESULTS: Doxorubicin and quercetin were successfully double-loaded with encapsulation efficiency (EE) of 43 ± 4.1% and 37 ± 4.5%, respectively, in native MCM-41. The post-synthetic carboxylation led to 49 ± 4.3% EE (DOX) and 36 ± 4.0% (Q) and double lowering of the cardiotoxicity on H9c2 (IC50 = 5.96 µm). Sustained release profiles over 72 h were achieved. CONCLUSIONS: A successful procedure was proposed for the efficient double loading of a hydrophilic drug and a hydrophobic drug. The carboxy-modified double-loaded nanosystems demonstrate a decreased in vitro cardiotoxicity of doxorubicin and can be considered as a potential chemotherapeutic formulation.

14.
Pharmaceutics ; 15(4)2023 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-37111772

RESUMO

The anthracycline antibiotic doxorubicin is a well-known antitumour agent, however its cardiotoxicity is a significant obstacle to therapy. The aim of the present study was to improve the safety of doxorubicin through its simultaneous encapsulation with a cardioprotective agent (resveratrol) in Pluronic micelles. The formation and double-loading of the micelles was performed via the film hydration method. Infrared spectroscopy proved the successful incorporation of both drugs. X-ray diffraction analyses revealed that resveratrol was loaded in the core, whereas doxorubicin was included in the shell. The double-loaded micelles were characterised by a small diameter (26 nm) and narrow size distribution, which is beneficial for enhanced permeability and retention effects. The in vitro dissolution tests showed that the release of doxorubicin depended on the pH of the medium and was faster than that of resveratrol. In vitro studies on cardioblasts showed the opportunity to reduce the cytotoxicity of doxorubicin through the presence of resveratrol in double-loaded micelles. Higher cardioprotection was observed when the cells were treated with the double-loaded micelles compared with referent solutions with equal concentrations of both drugs. In parallel, treatments of L5178 lymphoma cells with the double-loaded micelles revealed that the cytotoxic effect of doxorubicin was enhanced. Thus, the study demonstrated that the simultaneous delivery of doxorubicin and resveratrol via the micellar system enabled the cytotoxicity of doxorubicin in lymphoma cells and lowered its cardiotoxicity in cardiac cells.

15.
Pharmaceutics ; 14(12)2022 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-36559117

RESUMO

The present study is focused on the development of cannabidiol-loaded polymeric nanomicelles as a drug delivery system with neuroprotective effects. Cannabidiol was loaded in Pluronic micelles (Pluronic P123 or its combination with Pluronic F127) possessing an average diameter smaller than 50 nm and high encapsulation efficiency for the hydrophobic drug (80% and 84%, respectively). The successful encapsulation and transformation of cannabidiol in amorphous phase were observed by IR spectroscopy and X-ray diffraction, respectively. Studies with neuroblastoma cells (SH-SY5Y and Neuro-2a) showed that the pure cannabidiol caused a dose-dependent reduction of cell viability, whereas its loading into the micelles decreased cytotoxicity. Further, neuroprotective effects of pure and micellar cannabidiol were examined in a model of H2O2-induced oxidative stress in both neuroblastoma cells. The pre-treatment of cell lines with cannabidiol loaded into the mixed Pluronic P123/F127 micelles exerted significantly stronger protection against the oxidative stress compared to pure cannabidiol and cannabidiol in single Pluronic P123 micelles. Interestingly, the empty mixed P123/F127 micelles demonstrated protective activity against the oxidative stress. In conclusion, the study revealed the opportunity to formulate a new drug delivery system of cannabidiol, in particular nanosized micellar aqueous dispersion, that could be considered as a perspective platform for cannabidiol application in neurodegenerative diseases.

16.
ACS Omega ; 7(47): 43306-43315, 2022 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-36467919

RESUMO

ZnO doped with transition metals (Co, Fe, or Ni) that have non-compensated electron spins attracts particular interest as it can induce various magnetic phenomena and behaviors. The advanced atomic layer deposition (ALD) technique makes it possible to obtain very thin layers of doped ZnO with controllable thicknesses and compositions that are compatible with the main microelectronic technologies, which further boosts the interest. The present study provides an extended analysis of the magneto-optical MO Kerr effect and the dielectric properties of (Co, Fe, or Ni)-doped ZnO films prepared by ALD. The structural, magneto-optical, and dielectric properties were considered in relation to the technological details of the ALD process and the corresponding dopant effects. All doped samples show a strong MO Kerr behavior with a substantial magnetization response and very high values of the Kerr polarization angle, especially in the case of ZnO/Fe. In addition, the results give evidence that Fe-doped ZnO also demonstrates a ferroelectric behavior. In this context, the observed rich and versatile physical nature and functionality open up new prospects for the application of these nanostructured materials in advanced electronic, spintronic, and optical devices.

17.
Nanomaterials (Basel) ; 12(21)2022 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-36364676

RESUMO

The present paper reports on MnCoFeO4 spinels with peculiar composition and their catalytic behavior in the reactions of complete oxidation of hydrocarbons. The samples were synthesized by solution combustion method with sucrose and citric acid as fuels. All samples were characterized by powder X-ray diffraction, N2-physisorption, scanning electron microscopy, thermal analysis, X-ray photoelectron spectroscopy, and Mössbauer spectroscopy. The catalytic properties of the spinels with Mn:Co:Fe = 1:1:1 composition were studied in reactions of complete oxidation of methane, propane, butane, and propane in the presence of water as model pollutants. Both prepared catalysts are nanosized materials. The slight difference in the compositions, structure, and morphology is due to the type of fuel used in the synthesis reaction. The spinel, prepared with sucrose, shows a higher specific surface area, pore volume, higher amount of small particles fraction, higher thermal stability, and as a result, more exposed active sites on the sample surface that lead to higher catalytic activity in the studied oxidation reactions. After the catalytic tests, both samples do not undergo any substantial phase and morphological changes; thus, they could be applied in low-temperature hydrocarbon oxidation reactions.

18.
Polymers (Basel) ; 14(19)2022 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-36236062

RESUMO

Here, we report results on the magnetic and microwave properties of polycrystalline Y-type hexaferrite synthesized by sol-gel auto-combustion and acting as a filler in a composite microwave-absorbing material. The reflection losses in the 1-20 GHz range of the Y-type hexaferrite powder dispersed homogeneously in a polymer matrix of silicon rubber were investigated in the absence and in the presence of a magnetic field. A permanent magnet was used with a strength of 1.4 T, with the magnetic force lines oriented perpendicularly to the direction of the electromagnetic wave propagation. In the case of using an external magnetic field, an extraordinary result was observed. The microwave reflection losses reached a maximum value of 35.4 dB at 5.6 GHz in the Ku-band without a magnetic field and a maximum value of 21.4 dB at 8.2 GHz with the external magnetic field applied. The sensitivity of the microwave properties of the composite material to the external magnetic field was manifested by the decrease of the reflected wave attenuation. At a fixed thickness, tm, of the composite, the attenuation peak frequency can be adjusted to a certain value either by changing the filling density or by applying an external magnetic field.

19.
Nanomaterials (Basel) ; 12(12)2022 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-35745432

RESUMO

In the present study, we report on the facile prepared nanocomposites of reduced graphene oxide RGO with Cu and Ag. The synthesis was performed through an environmentally friendly and easy method by simultaneous reduction in solutions containing Cu2+ or Ag+ and graphene oxide (GO) using zinc powder as a reducing agent in aqueous acidic media. The composites are characterized by powder X-ray diffraction, low-temperature nitrogen adsorption, X-ray photoelectron and FTIR and Raman spectroscopies, as well as Scanning and Transmission electron microscopies. The antibacterial activity of the composites was tested for Staphylococcus aureus, Escherichia coli and antifungal activity for Candida albicans. The cytotoxicity of the materials was studied towards two types of eukaryotic cells-MDCK II and A549 cell lines. The composites obtained consist of homogeneously distributed Cu and Ag nanoparticles on the surface of graphene sheets and manifest good antimicrobial activity and high cytotoxicity. The results clearly show that both metal-RGO composites can be successfully used as antimicrobial and anticancer agents.

20.
ACS Appl Mater Interfaces ; 14(1): 873-890, 2022 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-34932905

RESUMO

Nickel-decorated mesoporous cerium-iron oxide composites were synthesized by a combination of incipient wetness impregnation and template-assisted hydrothermal techniques. The effects of the Fe/Ce ratio and the calcination temperature of cerium-iron oxides on the phase composition, texture, structure, and redox properties of the composites were studied by a combination of N2 physisorption, XRD, high-resolution transmission electron microscopy, SEM, Mössbauer, Raman, XPS, ultraviolet-visible and FTIR spectroscopies, H2-temperature-programmed reduction, and total oxidation of ethyl acetate as a catalytic test. The combined physicochemical characterization and in situ FTIR investigation of methanol decomposition was used for a proper understanding of the microstructure of the Ni/FeCe oxide composites and the mechanism of the reaction occurring on them. The complex role of the FeCe support in the stabilization of highly dispersed Ni particles, the generation of surface intermediates, and the impact of the support phase transformation under the reaction medium are discussed.

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