Sign in to use this feature.

Years

Between: -

Subjects

remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline

Journals

remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline

Article Types

Countries / Regions

remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline

Search Results (2,998)

Search Parameters:
Keywords = core-shell

Order results
Result details
Results per page
Select all
Export citation of selected articles as:
14 pages, 10281 KiB  
Article
Electro-Oxidation of Glycerol on Core–Shell M@Pt/C (M = Co, Ni, Sn) Catalysts in Alkaline Medium
by Rudyere Nascimento Silva, Leandro Aparecido Pocrifka, Ermete Antolini and Raimundo Ribeiro Passos
Energies 2025, 18(2), 305; https://doi.org/10.3390/en18020305 (registering DOI) - 11 Jan 2025
Abstract
This study explores the development of core–shell electrocatalysts for efficient glycerol oxidation in alkaline media. Carbon-supported M@Pt/C (M = Co, Ni, Sn) catalysts with a 1:1 atomic ratio of metal (M) to platinum (Pt) were synthesized using a facile sodium borohydride reduction method. [...] Read more.
This study explores the development of core–shell electrocatalysts for efficient glycerol oxidation in alkaline media. Carbon-supported M@Pt/C (M = Co, Ni, Sn) catalysts with a 1:1 atomic ratio of metal (M) to platinum (Pt) were synthesized using a facile sodium borohydride reduction method. The analysis confirmed the formation of the desired core–shell structure, with Pt dominating the surface as evidenced by energy-dispersive X-ray spectroscopy (EDS). X-ray diffraction (XRD) revealed the presence of a face-centered cubic (fcc) Pt structure for Co@Pt/C and Ni@Pt/C. Interestingly, Sn@Pt/C displayed a PtSn alloy formation indicated by shifted Pt peaks and the presence of minor Sn oxide peaks. Notably, no diffraction peaks were observed for the core metals, suggesting their amorphous nature. Electrocatalytic evaluation through cyclic voltammetry (CV) revealed superior glycerol oxidation activity for Co@Pt/C compared to all other catalysts. The maximum current density followed the order Co@Pt/C > Ni@Pt/C > Sn@Pt/C > Pt/C. This highlights the effectiveness of the core–shell design in enhancing activity. Furthermore, Sn@Pt/C displayed remarkable poisoning tolerance attributed to a combined effect: a bifunctional mechanism driven by Sn oxides and an electronic effect within the PtSn alloy. These findings demonstrate the significant potential of core–shell M@Pt/C structures for designing highly active and poisoning-resistant electrocatalysts for glycerol oxidation. The presented approach paves the way for further development of optimized catalysts with enhanced performance and stability aiming at future applications in direct glycerol fuel cells. Full article
(This article belongs to the Special Issue Advances in Materials for Electrochemical Energy Applications 2024)
Show Figures

Figure 1

17 pages, 4522 KiB  
Article
The Temperature-Dependent Tight Binding Theory Modelling of Strain and Composition Effects on the Electronic Structure of CdSe- and ZnSe-Based Core/Shell Quantum Dots
by Derya Malkoç and Hilmi Ünlü
Materials 2025, 18(2), 283; https://doi.org/10.3390/ma18020283 - 10 Jan 2025
Viewed by 237
Abstract
We propose a temperature-dependent optimization procedure for the second-nearest neighbor (2NN) sp3s* tight-binding (TB) theory parameters to calculate the effects of strain, structure dimensions, and alloy composition on the band structure of heterostructure spherical core/shell quantum dots (QDs). We integrate [...] Read more.
We propose a temperature-dependent optimization procedure for the second-nearest neighbor (2NN) sp3s* tight-binding (TB) theory parameters to calculate the effects of strain, structure dimensions, and alloy composition on the band structure of heterostructure spherical core/shell quantum dots (QDs). We integrate the thermoelastic theory of solids with the 2NN sp3s* TB theory to calculate the strain, core and shell dimensions, and composition effects on the band structure of binary/ternary CdSe/Cd(Zn)S and ZnSe/Zn(Cd)S QDs at any temperature. We show that the 2NN sp3s* TB theory with optimized parameters greatly improves the prediction of the energy dispersion curve at and in the vicinity of L and X symmetry points. We further used the optimized 2NN sp3s* TB parameters to calculate the strain, core and shell dimensions, and composition effects on the nanocrystal bandgaps of binary/ternary CdSe/Cd(Zn)S and ZnSe/Zn(Cd)S core/shell QDs. We conclude that the 2NN sp3s* TB theory provides remarkable agreement with the measured nanocrystal bandgaps of CdSe/Cd(Zn)S and ZnSe/Zn(Cd)S QDs and accurately reproduces the energy dispersion curves of the electronic band structure at any temperature. We believe that the proposed optimization procedure makes the 2NN sp3s* TB theory reliable and accurate in the modeling of core/shell QDs for nanoscale devices. Full article
Show Figures

Graphical abstract

20 pages, 5015 KiB  
Review
Advancements in Oral Delivery Systems for Probiotics Based on Polysaccharides
by Zi-Dan Wang, Wei Zhang and Tian-Xin Liang
Polymers 2025, 17(2), 144; https://doi.org/10.3390/polym17020144 - 8 Jan 2025
Viewed by 488
Abstract
Probiotics are an essential dietary supplement for intestinal flora balance, inhibition of pathogenic bacteria and immune regulation. However, probiotic inactivation during gastrointestinal transportation remains a big challenge for oral administration. Hence, oral delivery systems (ODSs) based on polysaccharides have been constructed to protect [...] Read more.
Probiotics are an essential dietary supplement for intestinal flora balance, inhibition of pathogenic bacteria and immune regulation. However, probiotic inactivation during gastrointestinal transportation remains a big challenge for oral administration. Hence, oral delivery systems (ODSs) based on polysaccharides have been constructed to protect probiotics from harsh environments. Cellulose, chitosan, alginate and their derivates have been used to form a protective layer for probiotics. This review summarizes the superiority and application of polysaccharides in forming protective layers for probiotics. Meanwhile, ODS processes including extrusion, emulsion and spray drying are also summarized. The preparation technique mechanism, the microparticle formation process and especially the role polysaccharides serve in the preparation process are overviewed. Lastly, the need for cell viability retention during the dehydration and construction of core-shell ODS microparticles is emphasized in this review. Full article
(This article belongs to the Section Biobased and Biodegradable Polymers)
Show Figures

Figure 1

12 pages, 2716 KiB  
Article
Rheological Behavior of Oil Well Cement Slurries with Addition of Core/Shell TiO2@SiO2 Nanoparticles—Effect of Superplasticizer and Temperature
by Giovanni dos Santos Batista, Francisca Puertas, Antonio Shigueaki Takimi, Eleani Maria da Costa and Marta Palacios
Materials 2025, 18(2), 239; https://doi.org/10.3390/ma18020239 - 8 Jan 2025
Viewed by 323
Abstract
This study investigates the rheological behavior of oil well cement pastes (OWCPs) modified with core/shell TiO2@SiO2 (nTS) nanoparticles and polycarboxylate-ether (PCE) superplasticizers at different temperatures (25, 45, and 60 °C). Results show that nTS particles increased static and dynamic yield [...] Read more.
This study investigates the rheological behavior of oil well cement pastes (OWCPs) modified with core/shell TiO2@SiO2 (nTS) nanoparticles and polycarboxylate-ether (PCE) superplasticizers at different temperatures (25, 45, and 60 °C). Results show that nTS particles increased static and dynamic yield stresses and the apparent viscosity of the cement slurries due to an increased solid volume fraction and reduced free water availability. The increase in the slurry dispersion by adding PCE superplasticizers enhanced the effect of the nanoparticles on the rheological parameters. Oscillation rheometry demonstrated that nTS nanoparticles enhanced the structural buildup, while PCE retarded hydration. Furthermore, slurries hydrated at 60 °C experienced higher initial values of the elastic modulus and a faster exponential increase in this rheological parameter due to the acceleration of the cement hydration. Full article
Show Figures

Figure 1

14 pages, 5040 KiB  
Article
A Solar-Heated Phase Change Composite Fiber with a Core–Shell Structure for the Recovery of Highly Viscous Crude Oil
by Chenxin Lin, Yifan Wang, Cenyu Liu, Kaiyue Meng, Endong Chang, Xiaowen Wu and Jiancheng Wang
Polymers 2025, 17(2), 135; https://doi.org/10.3390/polym17020135 - 8 Jan 2025
Viewed by 324
Abstract
Due to the high viscosity and low fluidity of viscous crude oil, how to effectively recover spilled crude oil is still a major global challenge. Although solar thermal absorbers have made significant progress in accelerating oil recovery, its practical application is largely restricted [...] Read more.
Due to the high viscosity and low fluidity of viscous crude oil, how to effectively recover spilled crude oil is still a major global challenge. Although solar thermal absorbers have made significant progress in accelerating oil recovery, its practical application is largely restricted by the variability of solar radiation intensity, which is influenced by external environmental factors. To address this issue, this study created a new composite fiber that not only possesses solar energy conversion and storage capabilities but also facilitates crude oil removal. PF@PAN@PEG was obtained by coaxial electrospinning processing, with PEG within PAN fibers, and a coating layer was applied to the fiber surface to impart oleophilicity and hydrophobicity. PF@PAN@PEG exhibited a high latent heat value (77.12 J/g), high porosity, and excellent photothermal conversion and oil storage capabilities, significantly reducing the viscosity of crude oil. PF@PAN@PEG can adsorb approximately 11.65 g/g of crude oil under sunlight irradiation. Notably, due to the encapsulation of PEG, PF@PAN@PEG can continuously maintain the crude oil at a phase change temperature by releasing latent heat under specific conditions, effectively reducing its viscosity with no PEG leakage at all. When solar light intensity varied, the crude oil collection efficiency increased by 21.99% compared to when no phase change material was added. This research offers a potential approach for the effective use of clean energy and the collection of viscous crude oil spill pollution. Full article
Show Figures

Graphical abstract

17 pages, 1658 KiB  
Article
UV-C and Nanomaterial-Based Approaches for Sulfite-Free Wine Preservation: Effects on Polyphenol Profile and Microbiological Quality
by Kamila Pachnowska, Jolanta Kochel-Karakulska, Adrian Augustyniak, Valentina Obradović, Ireneusz Ochmian, Sabina Lachowicz-Wiśniewska, Ireneusz Kapusta, Klaudia Maślana, Ewa Mijowska and Krzysztof Cendrowski
Molecules 2025, 30(2), 221; https://doi.org/10.3390/molecules30020221 - 8 Jan 2025
Viewed by 481
Abstract
Controlling the microorganisms employed in vinification is a critical factor for successful wine production. Novel methods aimed at lowering sulfites used for wine stabilization are sought. UV-C irradiation has been proposed as an alternative for reducing the viable cell count of microorganisms in [...] Read more.
Controlling the microorganisms employed in vinification is a critical factor for successful wine production. Novel methods aimed at lowering sulfites used for wine stabilization are sought. UV-C irradiation has been proposed as an alternative for reducing the viable cell count of microorganisms in wine and grape juice. Nevertheless, UV-C treatment poses the risk of altering the chemical properties of wine. Therefore, this study aimed to test and implement iron oxide–silica core–shell nanomaterial functionalized with TiO2 in UV-C treatment of white and red wines. Material for the study consisted of the synthesized nanocomposite, Saccharomyces cerevisiae as a model yeast, and Muscaris and Cabernet Cortis wines. The viability of yeasts under treatment, the physiochemical properties of wine, and polyphenol content were tested. Studies have shown that nanomaterial can modulate the effects of UV-C treatment regarding yeast viability and polyphenol content, and the effectiveness of the treatment depends on the wine type. These results open up discussion on the possible use of the proposed hurdle technology in winemaking to control the polyphenol composition and alcohol reduction. Full article
(This article belongs to the Special Issue Analyses and Applications of Phenolic Compounds in Food—2nd Edition)
Show Figures

Graphical abstract

16 pages, 4793 KiB  
Article
Simulation of Surface Segregation in Nanoparticles of Pt-Pd Alloys
by Jose Brito Correia and Ana Isabel de Sá
Crystals 2025, 15(1), 53; https://doi.org/10.3390/cryst15010053 - 7 Jan 2025
Viewed by 272
Abstract
Platinum (Pt) and palladium (Pd) are crucial in hydrogen energy technologies, especially in fuel cells, due to their high catalytic activity and chemical stability. Pt-Pd nanoparticles, produced through various methods, enhance catalytic performance based on their size, shape, and composition. These nanocatalysts excel [...] Read more.
Platinum (Pt) and palladium (Pd) are crucial in hydrogen energy technologies, especially in fuel cells, due to their high catalytic activity and chemical stability. Pt-Pd nanoparticles, produced through various methods, enhance catalytic performance based on their size, shape, and composition. These nanocatalysts excel in direct methanol fuel cells (DMFCs) and direct ethanol fuel cells (DEFCs) by promoting alcohol oxidation and reducing CO poisoning. Pt-Pd catalysts are also being explored for their oxygen reduction reaction (ORR) on the cathodic side of fuel cells, showing higher activity and stability than pure platinum. Molecular dynamics (MD) simulations have been conducted to understand the structural and surface energy effects of PdPt nanoparticles, revealing phase separation and chemical ordering, which are critical for optimizing these catalysts. Pd migration to the surface layer in Pt-Pd alloys minimizes the overall potential energy through the formation of Pd surface monolayers and Pt-Pd bonds, leading to a lower surface energy for intermediate compositions compared to that of the pure elements. The potential energy, calculated from MD simulations, increases with a decreasing particle size due to surface creation, indicating higher reactivity for smaller particles. A general contraction of the average distance to the nearest neighbour atoms was determined for the top surface layers within the nanoparticles. This research highlights the significant impact of Pd segregation on the structural and surface energy properties of Pt-Pd nanoparticles. The formation of Pd monolayers and the resulting core–shell structures influence the catalytic activity and stability of these nanoparticles, with smaller particles exhibiting higher surface energy and reactivity. These findings provide insights into the design and optimization of Pt-Pd nanocatalysts for various applications. Full article
Show Figures

Figure 1

13 pages, 4139 KiB  
Article
Microstructural, Morphological, and Magnetic Effects of NiFe2O4 Shell Formation Around Nanospherical ZnFe2O4 Cores
by Marija Šuljagić, Vuk Uskoković, Lukasz Kilanski, Sabina Lewinska, Abdul Khaliq, Anna Ślawska-Waniewska, Aleksandar Kremenović, Vladimir Pavlović, Dejan A. Jeremić and Ljubica Andjelković
Magnetochemistry 2025, 11(1), 2; https://doi.org/10.3390/magnetochemistry11010002 - 5 Jan 2025
Viewed by 410
Abstract
First-row transition metal oxides have relatively modest magnetic properties compared to those of permanent magnets based on rare earth elements. However, there is a hope that this gap might be bridged via proper compositional and structural adjustments. Bi-magnetic nanostructures with homogeneous interfaces often [...] Read more.
First-row transition metal oxides have relatively modest magnetic properties compared to those of permanent magnets based on rare earth elements. However, there is a hope that this gap might be bridged via proper compositional and structural adjustments. Bi-magnetic nanostructures with homogeneous interfaces often exhibit a combination or synergy of properties of both phases, resulting in improved performance compared to their monophasic magnetic counterparts. To gain a deeper insight into these complex structures, a bi-magnetic nanostructured material composed of superparamagnetic nanoparticles comprising a zinc ferrite core and a nickel ferrite shell was synthesized using the seed-mediated growth approach. The resulting ZnFe2O4@NiFe2O4 core–shell nanoparticles were characterized using a series of experimental techniques and were compared to the ZnFe2O4 cores. Most importantly, the formation of the NiFe2O4 shell around the ZnFe2O4 core improved the net crystallinity of the material and altered the particle morphology by reducing the convexity of the surface. Simultaneously, the magnetic measurements demonstrated the coherence of the interface between the core and the shell. These effects combined led to improved spin coupling and stronger magnetism, as evidenced by higher saturation magnetization and the doubling of the blocking temperature for the ZnFe2O4@NiFe2O4 core–shell particles relative to the ZnFe2O4 cores. Full article
Show Figures

Figure 1

23 pages, 2980 KiB  
Article
Nebulized Hybrid Nanoarchaeosomes: Anti-Inflammatory Activity, Anti-Microbial Activity and Cytotoxicity on A549 Cells
by Sofia Giuliana Guerin Stabile, Noelia Perez, Horacio Emanuel Jerez, Yamila Roxana Simioni, Estefanía Butassi, Martin Daniel Mizrahi, Matias Leonardo Nobile, Ana Paula Perez, Maria Jose Morilla, Leticia Herminia Higa and Eder Lilia Romero
Int. J. Mol. Sci. 2025, 26(1), 392; https://doi.org/10.3390/ijms26010392 - 4 Jan 2025
Viewed by 662
Abstract
The properties of two hybrid nanoarchaeosomes (hybrid nanoARCs) made of archaeolipids extracted from the halophilic archaea Halorubrum tebenquichense and combining the properties of archaeolipid bilayers with metallic nanoparticles are explored here. BS-nanoARC, consisting of a nanoARC loaded with yerba mate (Ilex paraguariensis) [...] Read more.
The properties of two hybrid nanoarchaeosomes (hybrid nanoARCs) made of archaeolipids extracted from the halophilic archaea Halorubrum tebenquichense and combining the properties of archaeolipid bilayers with metallic nanoparticles are explored here. BS-nanoARC, consisting of a nanoARC loaded with yerba mate (Ilex paraguariensis) extract (YME)-biogenic silver nanoparticles (BSs), and [BS + BS-nanoARC], consistent of a BS-nanoARC core covered by an outer shell of BSs, were structurally characterized and their therapeutic activities screened. By employing 109 ± 5 µg gallic acid equivalents (GAEs) and 73.4 µg chlorogenic acid/ YME mg as a silver reductive agent, spherical, heterogeneously sized (~80 nm diameter), −27 mV ζ potential, 90% Ag0 and λmax 420 nm BSs were obtained. We further prepared ~100–200 nm diameter, −57 mV ζ potential BS-nanoARC and ~300 nm diameter, −37 mV ζ potential [BS + BS-nanoARCs]. Freshly prepared and nebulized BS-nanoARCs reduced the release of TNF-α, IL-6 and IL-8 by LPS-irritated THP-1-macrophages and were highly anti-planktonic against S. aureus (MIC90: 13 ± 0.8 µg Ag/mL). While the nanoARCs and BS-nanoARCs were innocuous, freshly prepared [BS + BS-nanoARCs] magnified the cytotoxicity of BSs (IC50 12 µg Ag/mL vs. IC50 ~36 µg Ag/mL) on A549 cells. Such cytotoxicity remained after 30 days in the dark at 4 °C, while that of BSs was lost. Freshly prepared BSs also lost activity upon nebulization, whereas freshly prepared [BS + BS-nanoARCs] did not. However, the cytotoxicity of the [BS + BS-nanoARCs] was also lost when nebulized after 30 days of storage. Despite the harmful effects of storage and mechanical stress on the structure of the more active [BS + BS-nanoARCs], hybrid nanoARCs are promising examples of nanomedicines combining the properties of archaeolipids with antimicrobial silver nanoparticles and anti-inflammatory polyphenols that could complement oncologic therapies, reducing the usage of classical antitumoral agents, corticosteroids, and, importantly, of antibiotics, as well as their waste. Full article
(This article belongs to the Special Issue Recent Research on Novel Lipid-Based Nano Drug Delivery Systems)
Show Figures

Figure 1

13 pages, 3746 KiB  
Article
A Hierarchical Core-Shell Structure of NiO@Cu2O-CF for Effective Non-Enzymatic Electrochemical Glucose Detection
by Yueyun Huang, Jiahua You, Yingru Ding, Yun Xie, Ting Wang, Fanglong Zhu, Weiping Gong and Zhenting Zhao
Nanomaterials 2025, 15(1), 47; https://doi.org/10.3390/nano15010047 - 30 Dec 2024
Viewed by 404
Abstract
Non-enzymatic glucose detection is an effective strategy to control the blood glucose level of diabetic patients. A novel hierarchical core–shell structure of nickel hydroxide shell coated copper hydroxide core based on copper foam (Ni(OH)2@Cu(OH)2-CF) was fabricated and derived from [...] Read more.
Non-enzymatic glucose detection is an effective strategy to control the blood glucose level of diabetic patients. A novel hierarchical core–shell structure of nickel hydroxide shell coated copper hydroxide core based on copper foam (Ni(OH)2@Cu(OH)2-CF) was fabricated and derived from NiO@Cu2O-CF for glucose sensing. Cyclic voltammetry and amperometry experiments have demonstrated the efficient electrochemical catalysis of glucose under alkaline conditions. The measurement displays that the fabricated sensor exhibits a detection scale of 0.005–4.5 mM with a detection sensitivity of 4.67 µA/µM/cm2. It has remarkable response/recovery times in respect of 750 μM glucose (1.0 s/3.5 s). Moreover, the NiO@Cu2O-CF shows significant selectivity, reliable reproducibility and long-term stability for glucose determination, suggesting it is a suitable candidate for further applications. Full article
(This article belongs to the Special Issue Design and Applications of Heterogeneous Nanostructured Materials)
Show Figures

Graphical abstract

12 pages, 7218 KiB  
Article
Fabrication and Characterization of Pt-Pr6O11 Nano Cathode Electrode for Polymer Electrolyte Membrane Fuel Cells via Co-Sputtering Method
by Ki Won Hong, Ye Rim Kwon, Dong Kun Song, Do Yeong Jung, Byung Kyu Kang, Soon Ki Kwon, Sangbong Ryu and Gu Young Cho
Sustainability 2025, 17(1), 198; https://doi.org/10.3390/su17010198 - 30 Dec 2024
Viewed by 666
Abstract
In this study, the performance and durability of polymer electrolyte membrane fuel cells (PEMFCs) were improved using a Pt-Pr6O11 composite electrode fabricated through a co-sputtering technique. Platinum (Pt), widely used as the catalyst material in PEMFCs, often faces stability issues [...] Read more.
In this study, the performance and durability of polymer electrolyte membrane fuel cells (PEMFCs) were improved using a Pt-Pr6O11 composite electrode fabricated through a co-sputtering technique. Platinum (Pt), widely used as the catalyst material in PEMFCs, often faces stability issues under various electrical load conditions. These issues require greater efforts to enhance PEMFC durability. Various approaches, including replacement of catalyst supports with electrically stable materials (such as metal oxides) or adoption of core-shell and alloy structures to stabilize Pt, have been attempted. In this research, a thin film electrode combining Pr6O11 and Pt was fabricated. Pr6O11, a lanthanide oxide, enhances the oxygen reduction reaction (ORR) through strong interactions with Pt, and its multi-valence state contributes to improved durability. Scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS) were employed to analyze the composition, morphology, and chemical characteristics of the electrodes. I-V curves and electrochemical impedance spectroscopies (EIS) were measured to evaluate electrochemical properties of fuel cells. A cyclic voltammetry (CV) test was conducted to calculate the electrochemical surface area of the cell. As a result, the incorporation of Pr6O11 improved the pristine cell performance by 7.6% and increased performance after degradation testing by 121% compared to Pt-only cases. This demonstrates the effectiveness of the Pt-Pr6O11 composite in enhancing both the initial performance and the durability of PEMFCs. Full article
Show Figures

Figure 1

11 pages, 4919 KiB  
Communication
SiO2@Fe(III)-Based Metal–Organic Framework Core–Shell Microspheres for Water-Purification-Based Photo-Fenton Processes
by Kaihong Liu, Yuanli Zhu, Tanyu Cheng, Guohua Liu and Chunxia Tan
Catalysts 2025, 15(1), 23; https://doi.org/10.3390/catal15010023 - 30 Dec 2024
Viewed by 359
Abstract
In this study, SiO2@MIL-88A(Fe) core–shell microspheres were successfully synthesized through a simple immobilization method for dye degradation via an MIL-88A(Fe)-mediated Fenton-like process. These microspheres were fabricated by in situ immobilizing MIL-88A(Fe) onto mesoporous organosilane spheres functionalized with -COOH groups. Structural analyses [...] Read more.
In this study, SiO2@MIL-88A(Fe) core–shell microspheres were successfully synthesized through a simple immobilization method for dye degradation via an MIL-88A(Fe)-mediated Fenton-like process. These microspheres were fabricated by in situ immobilizing MIL-88A(Fe) onto mesoporous organosilane spheres functionalized with -COOH groups. Structural analyses and characterizations confirmed the formation of well-defined MOF particles anchored on the silicate microspheres, with electron microscopy verifying their porous core–shell structure. The newly developed core–shell materials achieved a high degree of dye degradation, reaching up to 96% for 10 mg/L dye solutions in neutral aqueous conditions within 30 min at room temperature through the Fenton-like process. Furthermore, SiO2@MIL-88A(Fe) exhibited excellent stability and recyclability, maintaining its performance over at least seven reuse cycles with minimal loss of activity. This material is easy to synthesize as well as cost-effective and demonstrates significant potential for wastewater purification involving a range of four different dyes. Full article
(This article belongs to the Special Issue Catalysis on Zeolites and Zeolite-Like Materials, 3rd Edition)
Show Figures

Figure 1

16 pages, 2881 KiB  
Article
Preparation of Novel Slow-Release Acid Materials for Oilfield Development via Encapsulation
by Xinshu Sun, Chen Chen, Mingxuan Li, Yiming Yao, Baohua Guo and Jun Xu
Materials 2025, 18(1), 83; https://doi.org/10.3390/ma18010083 - 28 Dec 2024
Viewed by 484
Abstract
Acid-fracturing technology has been applied to form pathways between deep oil/gas resources and oil production pipelines. The acid fracturing fluid is required to have special slow-release performance, with no acidity at low temperatures, while steadily generating acid at high temperatures underground. At present, [...] Read more.
Acid-fracturing technology has been applied to form pathways between deep oil/gas resources and oil production pipelines. The acid fracturing fluid is required to have special slow-release performance, with no acidity at low temperatures, while steadily generating acid at high temperatures underground. At present, commercial acid systems in oilfields present problems such as the uncontrollable release effect, high costs, and significant pollution. In this research, we designed an innovative chloroformate material and investigated the release of the acid at various temperatures. This new chloroformate material reacts slowly with water at room temperature, and can completely react with water to form hydrochloric acid at high temperatures, without residual organic chlorine and other harmful substances; thus, it is suitable for use as an acid agent in oilfields. To isolate the acid-release core material from the outer water phase, we encapsulated the former with various materials, such as cross-linked polyacrylate or polystyrene, to obtain microcapsules. By slowly breaking and degrading the shell layer at a high temperature, the goal of no acid being released at low temperatures with slow acid generation at a high temperature was achieved. The microcapsules were prepared using radical polymerization and the phase separation method. Furthermore, scanning electron microscopy, differential scanning calorimetry, chemical titration analysis, and other methods were used to characterize the structure and the sustained acid release of microcapsules. The results of thermogravimetry and other experiments showed that the prepared microcapsules successfully coated the chloroformate material. In contrast to the bare material, the slow-release performance of the microcapsules was significantly improved, and the continuous acid generating time was able to reach more than 10 h. Under optimum conditions, microcapsules with a uniform particle size with a sustained-release acid core were prepared, and the encapsulation efficiency reached up to 60%. Compared with traditional acid-release systems, the new system prepared in this study has better acid-release performance at high temperatures, while the product is both clean and convenient to use. Multiple important parameters, such as microcapsule particle size, can also be controlled by varying the experimental conditions to meet the needs of different oil/gas extraction environments. In summary, we prepared a promising new and efficient slow-release acid generation system, which has unique practical significance for optimizing current oilfield acid-fracturing technology. Full article
Show Figures

Figure 1

15 pages, 5986 KiB  
Article
Metasurface-Coated Liquid Microlens for Super Resolution Imaging
by Tongkai Gu, Kang Wang, Anjiang Cai, Fan Wu, Yasheng Chang, Haiyan Zhao and Lanlan Wang
Micromachines 2025, 16(1), 25; https://doi.org/10.3390/mi16010025 - 27 Dec 2024
Viewed by 270
Abstract
Inspired by metasurfaces’ control over light fields, this study created a liquid microlens coated with a layer of Au@TiO2, Core-Shell nanospheres. Utilizing the surface plasmon resonance (SPR) effect of Au@TiO2, Core-Shell nanospheres, and the formation of photonic nanojets (PNJs), [...] Read more.
Inspired by metasurfaces’ control over light fields, this study created a liquid microlens coated with a layer of Au@TiO2, Core-Shell nanospheres. Utilizing the surface plasmon resonance (SPR) effect of Au@TiO2, Core-Shell nanospheres, and the formation of photonic nanojets (PNJs), this study aimed to extend the imaging system’s cutoff frequency, improve microlens focusing, enhance the capture capability of evanescent waves, and utilize nanospheres to improve the conversion of evanescent waves into propagating waves, thus boosting the liquid microlens’s super-resolution capabilities. The finite difference time domain (FDTD) method analyzed the impact of parameters including nanosphere size, microlens sample contact width, and droplet’s initial contact angle on super-resolution imaging. The results indicate that the full width at half maximum (FWHM) of the field distribution produced by the uncoated microlens is 1.083 times that of the field distribution produced by the Au@TiO2, Core-Shell nanospheres coated microlens. As the nanosphere radius, droplet contact angle, and droplet base diameter increased, the microlens’s light intensity correspondingly increased. These findings confirm that metasurface coating enhances the super-resolution capabilities of the microlens. Full article
Show Figures

Figure 1

16 pages, 3331 KiB  
Article
Magnetic Molecularly Imprinted Polymers with Hydrophilic Shells for the Selective Enrichment and Detection of Rosmarinic Acid in Aqueous Extraction
by Yanhui Wang, Linlin Yan and Guangyao Zheng
Plants 2025, 14(1), 56; https://doi.org/10.3390/plants14010056 - 27 Dec 2024
Viewed by 336
Abstract
Rosmarinic acid (RA) is a natural active compound widely found in many plants belonging to the family of Lamiaceae, Boraginaceae, and so on, which has various important bioactivities, including being anti-oxidative, anti-inflammatory, antiviral, etc. Herein, novel hydrophilic magnetic molecularly imprinted polymers [...] Read more.
Rosmarinic acid (RA) is a natural active compound widely found in many plants belonging to the family of Lamiaceae, Boraginaceae, and so on, which has various important bioactivities, including being anti-oxidative, anti-inflammatory, antiviral, etc. Herein, novel hydrophilic magnetic molecularly imprinted polymers (HMMIPs) with a regular core-shell structure were successfully developed using RA as a template molecule, acrylamide (AM) as a functional monomer, N-N ’methylenebisacrylamide (MBA) as a cross-linking agent, and water as the porogen. After a series of characterization and adsorption performance analyses, it was found that HMMIPs are hydrophilic with an adsorption capacity of 8.012 ± 0.54 mg/g, an imprinting factor of 3.64, and a selectivity coefficient of 2.63~2.91. Furthermore, the HMMIPs can be rapidly separated from other components under the influence of external magnetic fields. The HMMIPs were employed for the determination of RA present in the Perilla frutescens and Rosmarinus officinalis aqueous extract with recoveries of 88.2~107.3%. These results indicated that HMMIPs of RA have the benefits of straightforward operation, rapid adsorption, and high selectivity, rendering it an appropriate way for the expedient and selective isolation of RA in an intricate matrix. Full article
Show Figures

Graphical abstract

Back to TopTop