Next Issue
Volume 18, June-1
Previous Issue
Volume 18, May-1
 
 
materials-logo

Journal Browser

Journal Browser

Materials, Volume 18, Issue 10 (May-2 2025) – 248 articles

Cover Story (view full-size image): The oxidative dehydrogenation (ODH) of ethanol to acetaldehyde is an important production process. However, it tends to suffer from low activity, selectivity, and high costs. Herein, we have developed a new strategy for preparing mesoporous nitrogen-doped carbon catalysts. The C=O functional group on the catalyst surface is found to be the active center, with the introduction of nitrogen atoms reducing the adsorption capacity of acetaldehyde molecules on the active site, improving selectivity to acetaldehyde. This work reveals the structure–activity relationship of nitrogen-doped carbon-based catalysts in ethanol ODH, providing a theoretical basis for the development of efficient non-metallic carbon-based catalysts for this reaction. View this paper
  • Issues are regarded as officially published after their release is announced to the table of contents alert mailing list.
  • You may sign up for e-mail alerts to receive table of contents of newly released issues.
  • PDF is the official format for papers published in both, html and pdf forms. To view the papers in pdf format, click on the "PDF Full-text" link, and use the free Adobe Reader to open them.
Order results
Result details
Section
Select all
Export citation of selected articles as:
19 pages, 3833 KiB  
Article
Sustainable Alginate–Hydrochar Composite Beads for 2-Nitrophenol Adsorption in Batch and Fixed-Bed Systems
by Dalia Allouss, Nicolas Abatzoglou and Inès Esma Achouri
Materials 2025, 18(10), 2412; https://doi.org/10.3390/ma18102412 - 21 May 2025
Viewed by 264
Abstract
Addressing the removal of hazardous phenolic pollutants from water, this study introduces an eco-friendly adsorbent composed of waste-derived hydrochar immobilized in alginate beads (Alg/HC). The physicochemical properties of the Alg/HC beads were characterized using SEM, XRD, and FTIR, confirming hydrochar encapsulation and partial [...] Read more.
Addressing the removal of hazardous phenolic pollutants from water, this study introduces an eco-friendly adsorbent composed of waste-derived hydrochar immobilized in alginate beads (Alg/HC). The physicochemical properties of the Alg/HC beads were characterized using SEM, XRD, and FTIR, confirming hydrochar encapsulation and partial structural preservation. Batch studies revealed a maximum 2-nitrophenol (2-NP) adsorption capacity of 15.80 ± 0.62 mg/g at 30 mg/L of 2-NP, with kinetics best described by the Elovich and pseudo-second-order models. Freundlich isotherm fitting indicated multilayer adsorption on heterogeneous surfaces, likely governed by hydrogen bonding and π–π interactions. In a fixed-bed column system, Alg/HC beads demonstrated a continuous adsorption capacity of 6.84 ± 0.45 mg/g at 10 mg/L of 2-NP, with breakthrough behavior modeled by the Yoon–Nelson and Thomas equations. The beads maintained stable performance across four regeneration cycles using a mild water/ethanol desorption method. This work represents the first study to explore Alg/HC composites for 2-NP removal in both batch and continuous modes, demonstrating their potential as low-cost, regenerable adsorbents for tertiary treatment of phenolic industrial wastewater. Full article
(This article belongs to the Section Advanced Composites)
Show Figures

Graphical abstract

20 pages, 1744 KiB  
Review
Application of Modified Natural Zeolite—Clinoptilolite for Bacterial Control in the Environment
by Jasna Hrenović and Nevenka Rajić
Materials 2025, 18(10), 2411; https://doi.org/10.3390/ma18102411 - 21 May 2025
Viewed by 186
Abstract
Natural zeolites are highly effective adsorbents that can remove various metal cations which would otherwise contaminate the environment. However, different metal cations (Cu, Zn, and Ag) within their lattice or quaternary long-chain surfactant cations on their surface modify their affinity towards hazardous anions [...] Read more.
Natural zeolites are highly effective adsorbents that can remove various metal cations which would otherwise contaminate the environment. However, different metal cations (Cu, Zn, and Ag) within their lattice or quaternary long-chain surfactant cations on their surface modify their affinity towards hazardous anions and promote antibacterial activity in natural zeolites. Specifically, natural zeolites in their non-modified form lack intrinsic antibacterial characteristics. NZ is the most widespread natural zeolite. This review presents the antibacterial efficiency of NZ containing transition metals, nano oxides, and organics. This effect is nonspecific and primarily driven by the nutritional makeup of the medium rather than the species of pathogenic bacteria under study. Studies on using NZ-based disinfectants to clean up contaminated water and soil and using modified and purified NZ to protect health are also considered. By eliminating toxic ions and, when modified by these toxic cations, removing pathogens from the environment, natural NZ can serve a dual function, providing it with the distinctive characteristics of a sustainable material. Full article
Show Figures

Figure 1

24 pages, 4823 KiB  
Article
Bioactive Glass and Melittin Thin Films Deposited by MAPLE for Titanium Implant Functionalization
by Mihaela Dinu, Bogdan Bita, Anca Constantina Parau, Carmen Ristoscu and Irina Negut
Materials 2025, 18(10), 2410; https://doi.org/10.3390/ma18102410 - 21 May 2025
Viewed by 108
Abstract
The development of bioactive coatings for metallic implants is essential to enhance osseointegration and improve implant longevity. In this study, composite thin films based on bioactive glass and melittin were synthesized using the matrix-assisted pulsed laser evaporation technique and deposited onto titanium substrates. [...] Read more.
The development of bioactive coatings for metallic implants is essential to enhance osseointegration and improve implant longevity. In this study, composite thin films based on bioactive glass and melittin were synthesized using the matrix-assisted pulsed laser evaporation technique and deposited onto titanium substrates. The coatings were characterized using physicochemical analysis methods, including scanning electron microscopy, atomic force microscopy, contact angle measurements, Fourier transform infrared spectroscopy, energy-dispersive X-ray spectroscopy, and electrochemical impedance spectroscopy. Simulated body fluid immersion tests were also conducted to assess bioactivity over time. Scanning electron microscopy and atomic force microscopy revealed dense, irregular surface textures with nanoscale features and an average roughness of ~120 nm, favorable for cell adhesion. Contact angle measurements showed a significant shift from hydrophobic (~95° for bare titanium) to moderately hydrophilic (~62° for the bioglass and melittin coating) surfaces, indicating improved biocompatibility. Electrochemical impedance spectroscopy demonstrated enhanced corrosion resistance in simulated body fluid, with the coating exhibiting a ~45% decrease in impedance magnitude after 12 h of immersion, compared to only 4% for bare titanium. Fourier transform infrared spectroscopy and energy-dispersive X-ray spectroscopy analyses confirmed the progressive formation of a carbonated apatite layer after 7 days of simulated body fluid exposure, suggesting high bioactivity and osteoconductive potential. The combined effects of bioactive glass and melittin in the thin film structure offer promising applications in orthopedic and dental implants, enhancing both biological performance and structural integrity. Full article
Show Figures

Figure 1

18 pages, 25199 KiB  
Article
Uneven Hydrophilic–Hydrophobic Nanoflowers Enhancing Solar Interface Evaporation: Se-Doped Carbon Loaded with Gradient Distribution of CoSe/Co
by Linhui Jia, Zhenhao Liu, Hongxun Hao and Zhongxin Liu
Materials 2025, 18(10), 2409; https://doi.org/10.3390/ma18102409 - 21 May 2025
Viewed by 178
Abstract
Solar interface evaporation is a promising technology for sustainable freshwater acquisition. Regulating the hydrophilicity/hydrophobicity of the evaporator can optimize the water transport, heat transfer, and evaporation enthalpy during the evaporation process, thereby significantly improving the evaporation performance. The CoSe/Co-SeC nanoflower was prepared by [...] Read more.
Solar interface evaporation is a promising technology for sustainable freshwater acquisition. Regulating the hydrophilicity/hydrophobicity of the evaporator can optimize the water transport, heat transfer, and evaporation enthalpy during the evaporation process, thereby significantly improving the evaporation performance. The CoSe/Co-SeC nanoflower was prepared by high-temperature selenization of ZIF-67. Each petal of the nanoflower is loaded with a density-gradient distribution CoSe/Co, forming an uneven hydrophilic and hydrophobic surface that transitions from bottom hydrophilicity to top hydrophobicity. During the evaporation process, the hydrophilic bottom of the petals promotes rapid water supply, while the hydrophobic top of the petals protrudes from the water surface to form a large number of solid–liquid–gas three-phase interfaces. Therefore, water clusters activated by the strong hydrophilic sites at the bottom of the petals can reach the gas–liquid interface after a very short transmission distance and achieve water cluster evaporation. In addition, the nanoflower optimized the heat transfer at the solid–liquid interface and further promoted the increase in evaporation rate through micro-meniscus evaporation (MME). As a result, the evaporation rate and energy efficiency of the CoSe/Co-SeC evaporator are as high as 2.44 kg m−2 h−1 and 95.5%. This work passes controllable preparation of the gradient CoSe/Co-SeC and shows the enormous potential of micro-hydrophobic and hydrophilic regulation for improving solar interface evaporation performance. Full article
(This article belongs to the Special Issue Progress in Carbon-Based Materials)
Show Figures

Graphical abstract

19 pages, 3497 KiB  
Article
Design of Bi-Material Triangle Curved Beam Honeycomb Metamaterial with Tunable Poisson’s Ratio, Thermal Expansion, and Band Gap Characteristics
by Zelong Wang, Yong Cheng, Huichuan Zhao and Han Zhang
Materials 2025, 18(10), 2408; https://doi.org/10.3390/ma18102408 - 21 May 2025
Viewed by 174
Abstract
Metamaterials, owing to their exceptional properties such as a negative Poisson’s ratio, phonon band gap, and energy absorption, have garnered significant interest in aerospace, automotive transportation, and other domains. The increasing demand for metamaterial structures with diverse specialized attributes requires innovative design approaches. [...] Read more.
Metamaterials, owing to their exceptional properties such as a negative Poisson’s ratio, phonon band gap, and energy absorption, have garnered significant interest in aerospace, automotive transportation, and other domains. The increasing demand for metamaterial structures with diverse specialized attributes requires innovative design approaches. In this study, a novel bi-material triangular curved beam honeycomb metamaterial (BTBM) is designed, which exhibits a tunable Poisson’s ratio (PR), coefficient of thermal expansion (CTE), and band gap characteristics. These properties are intrinsically coupled through the geometric and material design of the bi-material triangular curved beam structure, meaning that adjustments to the unit cell configuration simultaneously influence PR, CTE, and band gap behavior. This dual-mode control offers versatile design strategies for multifunctional metamaterials. The energy band structure is calculated using finite element simulation analysis, and its accuracy is validated by computing the transmission characteristic curve. Numerical simulations were performed to systematically analyze the coupled effects of geometric parameters and material combinations on the PR and CTE. The results demonstrate significant tunability of these mechanical properties through parametric optimization. The results of this study provide valuable insights into the design and optimization of metamaterial structures with tailored properties for various applications. Full article
(This article belongs to the Section Materials Simulation and Design)
Show Figures

Figure 1

19 pages, 10410 KiB  
Article
Influence of Cu on the Mechanical and Shape Memory Properties of TiNi Alloys
by Luzhou Dong, Weifang Mann and Bo He
Materials 2025, 18(10), 2407; https://doi.org/10.3390/ma18102407 - 21 May 2025
Viewed by 103
Abstract
The significant phase transformation hysteresis in TiNi alloys limits their performance. To address this, copper (Cu) was added as an alloying element to reduce hysteresis. This study synthesized three compositions of Ti50Ni50−xCux (x = 0, 5, 7 [...] Read more.
The significant phase transformation hysteresis in TiNi alloys limits their performance. To address this, copper (Cu) was added as an alloying element to reduce hysteresis. This study synthesized three compositions of Ti50Ni50−xCux (x = 0, 5, 7 at.%) shape memory alloys (SMAs) via vacuum arc melting to optimize the Cu content. The alloys were homogenized through hot rolling to maintain stable mechanical and shape memory properties. The hot-rolled Ti50Ni45Cu5 alloy demonstrated excellent shape memory behavior, achieving 100% thermal recovery after one cycle at 4% and 6% strain and 99.2% recovery after six cycles at 4% strain. It also exhibited outstanding mechanical performance, with a tensile strength of 900 MPa and 40% elongation. Microscopic analysis using scanning electron microscopy (SEM) with energy-dispersive X-ray spectroscopy (EDS), electron backscatter diffraction (EBSD), and transmission electron microscopy (TEM) revealed that Cu preferentially segregates at grain boundaries, suppressing the formation of the Ti2(Ni,Cu) phase. This moderate segregation, combined with hot rolling, promotes the reprecipitation and uniform distribution of phases, reducing the likelihood of premature fracture caused by stress concentration during deformation. The moderate thickness and uniformly distributed martensite, as well as the Type II twins with strong deformation ability, significantly improved the shape memory properties of Ti50Ni45Cu5. This study provides valuable insights into the microscopic mechanisms influenced by Cu in TiNi alloys and proposes a novel strategy for controlling precipitate phases through adjustments in alloy composition and optimized processing conditions. Full article
(This article belongs to the Section Mechanics of Materials)
Show Figures

Figure 1

19 pages, 9889 KiB  
Article
Brazing of Thin-Walled Stainless Steel Using Environmentally Friendly Ni-Cr-P Electrodeposition: Degradation Mechanism of Brazed Joint and Corresponding Improvement Strategy
by Shubin Liu, Yuqi Luan and Ikuo Shohji
Materials 2025, 18(10), 2406; https://doi.org/10.3390/ma18102406 - 21 May 2025
Viewed by 96
Abstract
A new brazing process for thin-walled stainless steel was proposed by combining green and efficient Ni-Cr-P electrodeposition with brazing technology. Novel information was attained by analyzing the electrodeposited Ni-Cr-P interlayers and the brazed joints and characterizing them using a combination of advanced techniques. [...] Read more.
A new brazing process for thin-walled stainless steel was proposed by combining green and efficient Ni-Cr-P electrodeposition with brazing technology. Novel information was attained by analyzing the electrodeposited Ni-Cr-P interlayers and the brazed joints and characterizing them using a combination of advanced techniques. The incorporation mechanisms of impurities (i.e., oxygen and carbon) in the Ni-Cr-P interlayers electrodeposited from a Cr(III)–glycine solution were revealed. The oxygen mainly came from the Cr(III)–hydroxy complexes formed by the hydrolysis and olation between Cr(III) complexes and OH ions near the cathode. Glycine did not directly participate in the cathode reactions but decomposed on the anode surface. These byproducts (carbonyl compounds) were directly incorporated into the interlayers in a molecular pattern, forming a weak link to the metallic chromium. Brazing test results showed that a certain amount of Cr2O3 powder, formed by the decomposition of chromium hydroxides in the interlayers under high-temperature catalysis, would cause the degradation of the brazed joints. Using the step-wise brazing method, the brazing sheets were first annealed to eliminate the impurities by utilizing the strong reducing effect of hydrogen and the weak link characteristics between carbonyl compounds and metallic chromium atoms. An excellent joint with a shear strength of 63.0 MPa was obtained by subsequent brazing. The microstructural analysis showed that the brazed seam was mainly composed of a Ni-Fe-Cr solid solution, the Ni3P eutectic phase, and small quantities of the Ni5P2 phase scattered in the Ni3P eutectic phase. Fracture mode observations showed that the cracks extended along the interface between the brittle P-containing phase and the primary phase, resulting in fracture. Full article
(This article belongs to the Special Issue Microstructure Engineering of Metals and Alloys, 3rd Edition)
Show Figures

Figure 1

22 pages, 48320 KiB  
Article
The Synergistic Utilization of Glass Aggregates and Glass Powder on the Thermal and Mechanical Properties of Concrete
by Bo Wen, Huaizheng Wang, Guanyi Gao, Lu Zhang, Zhengyao Yu and Zhihao Wang
Materials 2025, 18(10), 2405; https://doi.org/10.3390/ma18102405 - 21 May 2025
Viewed by 138
Abstract
Enhancing the utilization rate of waste glass in concrete is crucial for achieving solid waste reduction and low carbon emissions in the construction industry. This study employs the method of simultaneously replacing fine aggregate and cementitious materials in concrete with glass sand and [...] Read more.
Enhancing the utilization rate of waste glass in concrete is crucial for achieving solid waste reduction and low carbon emissions in the construction industry. This study employs the method of simultaneously replacing fine aggregate and cementitious materials in concrete with glass sand and glass powder to prepare composite waste glass concrete (CGC). The compressive strength, alkali–silicate expansion, and thermal properties of CGC were investigated experimentally. The experimental results show that the pozzolanic activity of fine glass powder in CGC can effectively mitigate the ASR reaction, enhance glass utilization, and allow the glass content to reach up to 17.79% of the total concrete mass. The thermal conductivity of the compounded waste glass concrete decreased linearly with increasing temperature, and the specific heat capacity showed three distinct peaks in the range of 180–800 °C, which were caused by chemical dehydration, quartz phase transition, and CaCO3 decarbonization, respectively. Furthermore, to examine the impact of replacement mode on the high-temperature resistance of waste glass concrete, the residual strength, physical properties, and microstructure of the concrete were evaluated. It was found that the residual strength ratio of CGC (0.73) exhibited a distinct advantage at 600 °C. At this time, the melting effect of glass can reduce the pore size of concrete and transform large pores into capillary pores. However, as the temperature rises to 800 °C, the melting effect of glass no longer alleviates the high-temperature damage to concrete, and the degree of decomposition of hydration products determines the concrete strength. Full article
Show Figures

Graphical abstract

18 pages, 36054 KiB  
Review
A Review of Photonic Sintering of Non-Oxide Ceramics for Printed Electronics
by Luis Felipe Gerlein, Mohamad Hassan Taherian and Martin Bolduc
Materials 2025, 18(10), 2404; https://doi.org/10.3390/ma18102404 - 21 May 2025
Viewed by 130
Abstract
This review article provides a comprehensive analysis of the photonic sintering conditions necessary to process non-oxide ceramics, to obtain similar material properties when compared with those of thermally annealed ones, for various applications in printed electronics. This article presents a thorough examination of [...] Read more.
This review article provides a comprehensive analysis of the photonic sintering conditions necessary to process non-oxide ceramics, to obtain similar material properties when compared with those of thermally annealed ones, for various applications in printed electronics. This article presents a thorough examination of the scientific literature on this topic, discussing the principles of photonic sintering applied to non-oxide ceramics, its advantages over traditional post-processing methods, and a quantitative overview of the performance of devices fabricated with the crystalline materials obtained. Full article
(This article belongs to the Section Advanced and Functional Ceramics and Glasses)
Show Figures

Figure 1

21 pages, 3094 KiB  
Article
Modification of Natural and Synthetic Zeolites for CO2 Capture: Unrevealing the Role of the Compensation Cations
by Norberto J. Abreu, Andrés F. Jaramillo, Daniel F. A. Becker-Garcés, Christian Antileo, Rebeca Martínez-Retureta, Jimmy A. Martínez-Ruano, Jaime Ñanculeo, Matías M. Pérez and Mara Cea
Materials 2025, 18(10), 2403; https://doi.org/10.3390/ma18102403 - 21 May 2025
Viewed by 131
Abstract
The development of highly effective natural-based adsorbents to face the increasing rates of CO2 production and their delivery to the atmosphere are a big concern nowadays. For such purposes, synthetic and natural zeolites were modified via an ion exchange procedure to enhance [...] Read more.
The development of highly effective natural-based adsorbents to face the increasing rates of CO2 production and their delivery to the atmosphere are a big concern nowadays. For such purposes, synthetic and natural zeolites were modified via an ion exchange procedure to enhance the CO2 uptake. Samples were characterized by SEM, EDS, TGA and nitrogen adsorption at 77 K, showing the correct incorporation of the new metals; in addition, the CO2 adsorption isotherms were determined using a gas analyser. During the first stage, the role of the compensation cations for CO2 adsorption was assessed by modifying a pure ZSM-5 synthetic zeolite with different metal precursors present in salt solutions via an ion exchange procedure. Then, five samples were studied; the samples modified with bivalent cation precursors (Zn2+ and Cu2+) presented a higher adsorption uptake than those modified with a monovalent cation (Na+ and K+). Specifically, the substitution of the compensation cations for Cu2+ increased the CO2 capture uptake without affecting the surface properties of the zeolite. The results depict the prevalence of π-cation interactions enhanced by the field gradient induced by divalent cations and their lower ionic radii, if compared to monovalent ones. Subsequently, a natural zeolite was modified considering the best results of the previous phase. This Surface Response Methodology was implemented considering 11 samples by varying the concentration of the copper precursor and the time of the ion exchange procedure. A quantitative quadratic model to predict the adsorption uptake with an R2 of 0.92 was obtained. The results depicted the optimal conditions to modify the used natural zeolite for CO2 capture. The modification procedure implemented increased the CO2 adsorption capacity of the natural zeolite more than 20%, reaching an adsorption capacity of 75.8 mg CO2/g zeolite. Full article
(This article belongs to the Section Porous Materials)
Show Figures

Graphical abstract

13 pages, 21741 KiB  
Article
Laser Cladding for Diamond-Reinforced Composites with Low-Melting-Point Transition Layer
by Yongqian Chen, Yifei Du, Jialin Liu, Shanghua Zhang, Tianjian Wang, Shirui Guo, Yinghao Cui, Xiaolei Li, Bo Zheng, Yue Zhao and Lujun Cui
Materials 2025, 18(10), 2402; https://doi.org/10.3390/ma18102402 - 21 May 2025
Viewed by 92
Abstract
To address the graphitization of diamond induced by high temperatures during laser cladding of diamond-reinforced composites, this study proposes a laser cladding method utilizing Inconel 718 (IN718) nickel-based alloy as a transition layer which has a lower melting point than the substrate of [...] Read more.
To address the graphitization of diamond induced by high temperatures during laser cladding of diamond-reinforced composites, this study proposes a laser cladding method utilizing Inconel 718 (IN718) nickel-based alloy as a transition layer which has a lower melting point than the substrate of 45# steel. And then, in order to analyze the detailed characteristics of the samples, scanning electron microscopy (SEM), EDS, Raman spectral analyzer, super-depth-of-field microscope, and friction tests were used. Experimental study and the test results demonstrate that the IN718 transition layer enhances coating performance through dual mechanisms: firstly, its relatively low melting point (1392 °C) reduces the molten pool’s peak temperature, effectively suppressing thermal-induced graphitization of the diamond; on the other hand, simultaneously it acts as a diffusion barrier to inhibit Fe migration from the substrate and weaken Fe–C interfacial catalytic reactions. Microstructural analysis reveals improved diamond encapsulation and reduced interfacial sintering defects in coatings with the transition layer. Tribological tests confirm that samples with the transition layer L exhibit lower friction coefficients and significantly enhanced wear resistance compared to those without. This study elucidates the synergistic mechanism of the transition layer in thermal management optimization and interfacial reaction suppression, providing an innovative solution to overcome the high-temperature damage bottleneck in laser-clad diamond tools. Full article
(This article belongs to the Section Manufacturing Processes and Systems)
Show Figures

Figure 1

17 pages, 3165 KiB  
Article
Impact of Degraded Aviation Paints on the Aerodynamic Performance of Aircraft Skin
by Wojciech Żyłka, Andrzej Majka, Patrycja Skała, Zygmunt Szczerba, Bogumił Cieniek and Ireneusz Stefaniuk
Materials 2025, 18(10), 2401; https://doi.org/10.3390/ma18102401 - 21 May 2025
Viewed by 93
Abstract
This study investigates the degradation of aircraft paint and its impact on aerodynamic performance, using the PZL M-20 “Mewa” aircraft as a case study. Paint samples were collected from both damaged and intact areas of the airframe and analyzed using electron paramagnetic resonance [...] Read more.
This study investigates the degradation of aircraft paint and its impact on aerodynamic performance, using the PZL M-20 “Mewa” aircraft as a case study. Paint samples were collected from both damaged and intact areas of the airframe and analyzed using electron paramagnetic resonance (EPR) spectroscopy, scanning electron microscopy (SEM), and aerodynamic testing. One of the major challenges addressed in this work was the non-destructive identification of chemical aging effects in operational paint coatings and their correlation with aerodynamic behavior. The application of EPR spectroscopy in conjunction with real-world aerodynamic testing on naturally degraded surfaces represents an innovative approach that offers both scientific insight and practical guidance for maintenance practices. The results indicate significant deterioration in aerodynamic characteristics—such as increased drag and reduced lift—due to coating damage, particularly around riveted and bolted joints. EPR spectra revealed a notable increase in the density of unpaired electron spins in aged coatings, confirming ongoing oxidative degradation processes. While this study was limited to a single aircraft, the findings highlight the critical importance of regular inspection and maintenance of paint coatings to ensure flight safety and operational efficiency. Full article
(This article belongs to the Section Corrosion)
Show Figures

Graphical abstract

19 pages, 6248 KiB  
Article
One-Step Synthesis of Nitrogen-Doped TiO2 Heterojunctions and Their Visible Light Catalytic Applications
by Peng Lian, Aimiao Qin, Zhisen Liu, Hao Ma, Lei Liao, Kaiyou Zhang and Yingxi Qin
Materials 2025, 18(10), 2400; https://doi.org/10.3390/ma18102400 - 21 May 2025
Viewed by 105
Abstract
In this study, nitrogen-doped TiO2 heterojunction materials were successfully synthesized via a facile one-step solvothermal approach. A range of advanced characterization techniques were employed to thoroughly analyze the structural and compositional properties of the synthesized photocatalysts, and their application potential for tetracycline [...] Read more.
In this study, nitrogen-doped TiO2 heterojunction materials were successfully synthesized via a facile one-step solvothermal approach. A range of advanced characterization techniques were employed to thoroughly analyze the structural and compositional properties of the synthesized photocatalysts, and their application potential for tetracycline (TC) degradation under visible light was studied. The results indicated that N-doped TiO2 exhibited a well-defined hierarchical micro/nanostructure and formed an efficient anatase/rutile homogeneous heterojunction. The photocatalytic performance of N-TiO2 for TC degradation under visible light was significantly enhanced, achieving a degradation efficiency of up to 87% after 60 min of irradiation. This improvement could be attributed to the synergistic effects of optimal nitrogen doping, heterojunction formation, and the hierarchical micro/nanostructure, which collectively reduced the bandgap energy and suppressed the recombination rate of photogenerated carriers. Furthermore, density functional theory (DFT) calculations were conducted to systematically explore the impacts of substitutional and interstitial nitrogen doping on the energy band structure of TiO2. Full article
Show Figures

Figure 1

16 pages, 8970 KiB  
Article
Analysis of the Thermal Properties of Soft Silica Limestone Walls of Traditional Buildings in Central Poland
by Aleksandra Gorączko, Paula Szczepaniak and Marcin Gorączko
Materials 2025, 18(10), 2399; https://doi.org/10.3390/ma18102399 - 21 May 2025
Viewed by 87
Abstract
The challenge of thermally upgrading traditional stone masonry buildings is addressed through the analysis of a representative example typical of regional rural architecture in central Poland, constructed using soft silica limestone and clay mortar. These buildings, which form an important part of the [...] Read more.
The challenge of thermally upgrading traditional stone masonry buildings is addressed through the analysis of a representative example typical of regional rural architecture in central Poland, constructed using soft silica limestone and clay mortar. These buildings, which form an important part of the local cultural heritage, are increasingly becoming the subject of interdisciplinary research and conservation initiatives. This study presents a detailed characterization of the materials and architectural features specific to this building typology. Thermal transmittance calculations were performed and analyzed, with the use of THERM 7.6.1.0 software enabling precise modeling of the wall’s heterogeneous structure. The physical and thermal properties of natural materials—particularly soft silica limestone and clay—were taken into account. The analysis included evaluation of the heat transfer coefficient, temperature distribution, and heat flux density for a reference wall model, as well as for variants with both internal and external insulation layers. The study explores thermal comfort and energy performance within the broader context of preserving and reusing historic rural buildings. Furthermore, the findings are discussed in relation to current European energy efficiency regulations and heritage protection frameworks. The scientific value of this work lies in its context-specific, material-sensitive methodology and in providing practical insight into balancing energy retrofitting with architectural conservation. Full article
(This article belongs to the Special Issue Testing of Materials and Elements in Civil Engineering (4th Edition))
Show Figures

Figure 1

11 pages, 2446 KiB  
Article
Highly Stable, Flexible, Transparent Hybrid Strontium Titanate Conductive Thin Films with Embedded Cu Nanowires
by Ming Liu, Shihui Yu, Lijun Song, Jiesong Li and Jian Feng
Materials 2025, 18(10), 2398; https://doi.org/10.3390/ma18102398 - 21 May 2025
Viewed by 115
Abstract
To meet the stringent demands of next-generation flexible optoelectronic devices, a novel fabrication approach is employed that integrates the spray-coating of copper nanowires (Cu NWs) with the magnetron sputtering of SrTiO3 thin films, thereby yielding SrTiO3/Cu NWs/SrTiO3 hybrid thin [...] Read more.
To meet the stringent demands of next-generation flexible optoelectronic devices, a novel fabrication approach is employed that integrates the spray-coating of copper nanowires (Cu NWs) with the magnetron sputtering of SrTiO3 thin films, thereby yielding SrTiO3/Cu NWs/SrTiO3 hybrid thin films. The incorporation of the SrTiO3 layers results in improved optical performance, with the transmittance of the Cu NW network increasing from 83.5% to 84.2% and a concurrent reduction in sheet resistance from 16.9 Ω/sq to 14.5 Ω/sq. Moreover, after subjecting the hybrid thin films to 100 repeated tape-peeling tests and 2000 bending cycles with a bending radius of 5.0 mm, the resistance remains essentially unchanged, which underscores the films’ exceptional mechanical flexibility and robust adhesion. Additionally, the hybrid thin films are subjected to rigorous high-temperature, high-humidity, and oxidative conditions, where the resistance exhibits outstanding stability. These results substantiate the potential of the SrTiO3/Cu NWs/SrTiO3 hybrid thin films for integration into flexible and wearable electronic devices, delivering enhanced optoelectronic performance and long-term reliability under demanding conditions. Full article
(This article belongs to the Section Thin Films and Interfaces)
Show Figures

Figure 1

12 pages, 4364 KiB  
Article
Synergistic Nitrogen-Doping and Defect Engineering in Hard Carbon: Unlocking Ultrahigh Rate Capability and Long-Cycling Stability for Sodium-Ion Battery Anodes
by Na Li, Hongpeng Li and Haibo Huang
Materials 2025, 18(10), 2397; https://doi.org/10.3390/ma18102397 - 21 May 2025
Viewed by 100
Abstract
Hard carbon (HC) anodes for sodium-ion batteries (SIBs) face challenges such as sluggish Na⁺ diffusion kinetics and structural instability. Herein, we propose a synergistic nitrogen-doping and defect-engineering strategy to unlock ultrahigh-rate capability and long-term cyclability in biomass-derived hard carbon. A scalable synthesis route [...] Read more.
Hard carbon (HC) anodes for sodium-ion batteries (SIBs) face challenges such as sluggish Na⁺ diffusion kinetics and structural instability. Herein, we propose a synergistic nitrogen-doping and defect-engineering strategy to unlock ultrahigh-rate capability and long-term cyclability in biomass-derived hard carbon. A scalable synthesis route is developed via hydrothermal carbonization of corn stalk, followed by controlled pyrolysis with urea, achieving uniform nitrogen incorporation into the carbon matrix. Comprehensive characterization reveals that nitrogen doping introduces tailored defects, expands interlayer spacing, and optimizes surface pseudocapacitance. The resultant N-doped hard carbon (NC-2) delivers a remarkable reversible capacity of 259 mAh g−1 at 0.1 A g−1 with 91% retention after 100 cycles. And analysis demonstrates a dual Na⁺ storage mechanism combining surface-driven pseudocapacitive adsorption (89% contribution at 1.0 mV s−1) and diffusion-controlled intercalation facilitated by reduced charge transfer resistance (56.9 Ω) and enhanced ionic pathways. Notably, NC-2 exhibits exceptional rate performance (124.0 mAh g−1 at 1.0 A g−1) and sustains 95% capacity retention over 500 cycles at 1.0 A g−1. This work establishes a universal defect-engineering paradigm for carbonaceous materials, offering fundamental insights into structure–property correlations and paving the way for sustainable, high-performance SIB anodes. Full article
(This article belongs to the Special Issue Advanced Electrode Materials for Batteries: Design and Performance)
Show Figures

Figure 1

10 pages, 1467 KiB  
Communication
Monolayer TiAlTe3: A Perfect Room-Temperature Valleytronic Semiconductor
by Kang Jia, Chang-Wen Zhang, Zi-Ran Wang and Pei-Ji Wang
Materials 2025, 18(10), 2396; https://doi.org/10.3390/ma18102396 - 21 May 2025
Viewed by 70
Abstract
Investigating valley-related physics in rare intrinsic ferromagnetic materials with high-temperature stability and viable synthesis methods is of vital importance for advancing fundamental physics and information technology. Through first-principles calculations, we forecast that monolayer TiAlTe3 has superb structural stability, a ferromagnetic coupling mechanism [...] Read more.
Investigating valley-related physics in rare intrinsic ferromagnetic materials with high-temperature stability and viable synthesis methods is of vital importance for advancing fundamental physics and information technology. Through first-principles calculations, we forecast that monolayer TiAlTe3 has superb structural stability, a ferromagnetic coupling mechanism deriving from direct-exchange and superexchange interactions, and a high magnetic transition temperature. We observed spontaneous valley polarization of 103 meV in the bottom conduction band when monolayer TiAlTe3 is magnetized toward an out-of-plane orientation. Additionally, because of its powerful valley-contrasting Berry curvature, the anomalous valley Hall effect emerges under an in-plane electric field. The cooperation of ferromagnetic coupling, a high magnetic transition temperature, and spontaneous valley polarization makes monolayer TiAlTe3 a promising room-temperature ferrovalley material for use in nanoscale spintronics and valleytronics. Full article
(This article belongs to the Section Electronic Materials)
Show Figures

Figure 1

15 pages, 5437 KiB  
Article
Evaluation of Physical Properties of Ti-Doped BiFeO3 Thin Films Deposited on Fluorine Tin Oxide and Indium Tin Oxide Substrates
by Anel Rocío Carrasco-Hernández, Armando Reyes-Rojas, Gabriel Rojas-George, Antonio Ramírez-De la Cruz and Hilda Esperanza Esparza-Ponce
Materials 2025, 18(10), 2395; https://doi.org/10.3390/ma18102395 - 21 May 2025
Viewed by 77
Abstract
BiFeO3 is a fascinating material with a rhombohedral crystal structure (R3c) at room temperature. This unique structure makes it suitable for use in solar cells, as the interaction of light with the polarized octahedral enhances electron movement. Evaluating its properties [...] Read more.
BiFeO3 is a fascinating material with a rhombohedral crystal structure (R3c) at room temperature. This unique structure makes it suitable for use in solar cells, as the interaction of light with the polarized octahedral enhances electron movement. Evaluating its properties on different substrates helps to identify the specific characteristics of thin films. The thin films presented in this work were deposited using reactive RF cathodic sputtering with a homemade 1-inch diameter ceramic target. Their morphology, phase composition, optical, piezoelectric, and ferroelectric properties were evaluated. Fluorine Tin Oxide (FTO) and Indium Tin Oxide (ITO) substrates were used for the presented thin films. The thin films deposited on FTO displayed the “butterfly” behavior typically associated with ferroelectric materials. A d33 value of 2.71 nm/V was determined using SSPFM-DART mode. In contrast, the thin films deposited on ITO at 550 °C reached a maximum saturation polarization of 40.89 μC/cm2 and a remnant polarization of 44.87 μC/cm2, which are the highest values recorded, but did not present the typical “butterfly” behavior. As the grain size increased, the influence of charge defects became more pronounced, leading to an increase in the leakage current. Furthermore, the presence of secondary phases also contributed to this behavior. Full article
(This article belongs to the Special Issue The Optical, Ferroelectric and Dielectric Properties of Thin Films)
Show Figures

Graphical abstract

25 pages, 6810 KiB  
Article
Multiscale Topology Design Based on Non-Penalisation Smooth-Edged Material Distribution for Optimising Topology (SEMDOT)
by Jiye Zhou, Yun-Fei Fu and Kazem Ghabraie
Materials 2025, 18(10), 2394; https://doi.org/10.3390/ma18102394 - 20 May 2025
Viewed by 143
Abstract
This study presents an extension of the Smooth-Edged Material Distribution Optimisation Technique (SEMDOT) to multiscale topology optimisation (MSTO). While the SEMDOT has shown promise in producing smooth and fabrication-friendly structures in various single-scale problems, its application to multiscale design remains unexplored. To extend [...] Read more.
This study presents an extension of the Smooth-Edged Material Distribution Optimisation Technique (SEMDOT) to multiscale topology optimisation (MSTO). While the SEMDOT has shown promise in producing smooth and fabrication-friendly structures in various single-scale problems, its application to multiscale design remains unexplored. To extend SEMDOT to MSTO, a discrete sensitivity approach without penalisation is introduced, in which sensitivities are directly determined by classifying elements. Microstructural properties are computed using energy-based homogenisation with periodic boundary conditions (PBCs), enabling efficient and accurate prediction of effective elastic moduli. Physical fidelity of the smooth boundaries estimated by level-set functions are validated. Numerical results from 2D and 3D compliance minimization benchmarks demonstrate the effectiveness of the SEMDOT method, resulting in smooth boundaries between solid and void phases at both macro- and microscales, overcoming the jagged boundaries and grayscale issues seen in conventional methods. The results also show that the SEMDOT achieves comparable performance to other MSTO methods, with fewer iterations and reduced computational time. Full article
(This article belongs to the Special Issue New Insights into Additive Manufacturing for Materials and Structures)
Show Figures

Figure 1

20 pages, 3979 KiB  
Article
Experimental Study on Shear Characteristics of Filled Joints Anchored by Basalt Fiber-Reinforced Polymer Materials
by Hengjie Luan, Qingzhai Shi, Changsheng Wang, Yujing Jiang, Sunhao Zhang, Jianrong Liu and Kun Liu
Materials 2025, 18(10), 2393; https://doi.org/10.3390/ma18102393 - 20 May 2025
Viewed by 125
Abstract
Filled joints are widely found in natural rock masses and are one of the main factors causing rock mass engineering instability. The use of bolts can effectively control the shear slip of filled joints, research on bolts filled joints in the filling degree, [...] Read more.
Filled joints are widely found in natural rock masses and are one of the main factors causing rock mass engineering instability. The use of bolts can effectively control the shear slip of filled joints, research on bolts filled joints in the filling degree, and other key parameters of the influence of the law, to ensure the stability of the engineering rock body is of great significance. This paper presents shear experiments on bolted filled joints of Basalt Fiber-Reinforced Polymer (BFRP) materials with different joint roughness and filling degrees, while acoustic emission technology monitors the shear failure process of the specimens. The results show that the peak shear strength decreases with the increase in filling degree, and the peak shear strength decreases by 23.9% when the filling degree changes from 0 to 2.0 at 4 MPa and J2 conditions, while the normal stress, the Joint Roughness Coefficient (JRC) and the peak shear strength both show a positive correlation. The normal deformation of bolted filled joints exhibits three distinct evolutionary patterns depending on the filling degree, while both JRC and normal stress significantly influence the magnitude of shear dilatancy-shrinkage deformation. The shear resistance of BFRP bolts is mainly reflected in the post-peak plastic stage, and some of the fibers break during its shear deformation to form controlled yielding, with vertical and horizontal deformation controlled within 15.5~22.3 mm and 4.7~6.9 mm, respectively. The Acoustic Emission (AE) results show that the AE events are mainly in the post-peak plasticity stage, and the proportion is about the sum of the proportion of the other two phases, and this proportion increases with the increase in the filling degree. Full article
Show Figures

Figure 1

30 pages, 9195 KiB  
Article
Enhancing Sealing Performance Predictions: A Comprehensive Study of XGBoost and Polynomial Regression Models with Advanced Optimization Techniques
by Weiru Zhou and Zonghong Xie
Materials 2025, 18(10), 2392; https://doi.org/10.3390/ma18102392 - 20 May 2025
Viewed by 118
Abstract
Motors, as the core carriers of pollution-free power, realize efficient electric energy conversion in clean energy systems such as electric vehicles and wind power generation, and are widely used in industrial automation, smart home appliances, and rail transit fields with their low-noise and [...] Read more.
Motors, as the core carriers of pollution-free power, realize efficient electric energy conversion in clean energy systems such as electric vehicles and wind power generation, and are widely used in industrial automation, smart home appliances, and rail transit fields with their low-noise and zero-emission operating characteristics, significantly reducing the dependence on fossil energy. As the requirements of various application scenarios become increasingly complex, it becomes particularly important to accurately and quickly design the sealing structure of motors. However, traditional design methods show many limitations when facing such challenges. To solve this problem, this paper proposes hybrid models of machine learning that contain polynomial regression and optimization XGBOOST models to rapidly and accurately predict the sealing performance of motors. Then, the hybrid model is combined with the simulated annealing algorithm and multi-objective particle swarm optimization algorithm for optimization. The reliability of the results is verified by the mutual verification of the results of the simulated annealing algorithm and the particle swarm optimization algorithm. The prediction accuracy of the hybrid model for data outside the training set is within 2.881%. Regarding the prediction speed of this model, the computing time of ML is less than 1 s, while the computing time of FEA is approximately 9 h, with an efficiency improvement of 32,400 times. Through the cross-validation of single-objective optimization and multi-objective optimization algorithms, the optimal design scheme is a groove depth of 0.8–0.85 mm and a pre-tightening force of 80 N. The new method proposed in this paper solves the limitations in the design of motor sealing structures, and this method can be extended to other fields for application. Full article
(This article belongs to the Section Materials Simulation and Design)
Show Figures

Figure 1

15 pages, 9558 KiB  
Communication
Contact Load on the Current-Carrying Tribological Performance of Copper–Graphite Composites
by Jiayu Ye, Nenghui Wang, Haihong Wu, Chuanfeng Wang and Xiao Kang
Materials 2025, 18(10), 2391; https://doi.org/10.3390/ma18102391 - 20 May 2025
Viewed by 193
Abstract
This study investigates the current-carrying tribological properties and wear mechanisms of copper–graphite composites under varying contact loads. Two copper–graphite composites with different graphite content were prepared using the pressure sintering method. Current-carrying tribological tests were conducted at three distinct contact loads. Scanning electron [...] Read more.
This study investigates the current-carrying tribological properties and wear mechanisms of copper–graphite composites under varying contact loads. Two copper–graphite composites with different graphite content were prepared using the pressure sintering method. Current-carrying tribological tests were conducted at three distinct contact loads. Scanning electron microscopy, X-ray diffraction, laser confocal microscopy, and pin-on-disk tribological testing were utilized to examine the current-carrying tribological properties and the worn morphologies of the materials. The results indicate that, under the three contact loads, the friction coefficient of the copper–graphite materials ranged from 0.3 to 0.5, the wear rate was on the order of 10−13 m3/(N·m), the average voltage drop varied between 0.7 and 1.6 V, and the average electrical noise ranged from 0.2 to 0.9 mV. The wear mechanism included delamination wear and a minor amount of abrasive wear, and the lubricating film formed on the surface was mainly composed of C, PbO, and CuO. Notably, copper–graphite composites with lower graphite content exhibited superior hardness, electrical conductivity, and relative density compared to those with higher graphite content. At a contact load of 0.31 N, the copper–graphite composite containing 30wt% graphite demonstrated the most favorable current-carrying tribological performance, characterized by the lowest wear rate (1.09 × 10−13 m3/(N·m)), voltage drop (0.943 V), and electrical noise (0.234 mV). Full article
Show Figures

Figure 1

14 pages, 2395 KiB  
Article
Lunar Regolith Improvement by Inducing Interparticle Adhesion with Capillary Forces
by Karol Brzeziński, Joanna Julia Sokołowska and Bartłomiej Przybyszewski
Materials 2025, 18(10), 2390; https://doi.org/10.3390/ma18102390 - 20 May 2025
Viewed by 142
Abstract
This paper concerns the assessment of the lunar regolith ability to consolidate in the presence of liquid water and develop and sustain cohesion after drying. This type of cohesion originates from interparticle adhesion and can be potentially improved through grading modification. The research [...] Read more.
This paper concerns the assessment of the lunar regolith ability to consolidate in the presence of liquid water and develop and sustain cohesion after drying. This type of cohesion originates from interparticle adhesion and can be potentially improved through grading modification. The research was conducted using the lunar regolith simulant (EAC-1A) reproducing the PSD of real lunar soil delivered from the Moon. LRS was subjected to water and elevated temperature (equal to the highest temperature on the Moon) to produce specimens of consolidated material, CCR (Capillary-Consolidated Regolith) and to test flexural strength. In order to adapt to potentially small stresses, tests were performed according to the modified EN 196-1 procedure intended for Portland cement testing: specimens scaled to 20 mm × 20 mm × 80 mm (new molds with Polytetrafluoroethylene/Teflon® coatings reducing adhesion were created), supports spacing in the three-point flexural test reduced to 50 mm and apparatus adjusted to precisely apply small loads. CCR developed flexural strength exceeding 0.025 MPa. Then, analogous tests were performed using LRS subjected to grinding in a disc mill prior to consolidation. It was shown that simple mechanical grinding enabled the improvement of interparticle adhesion with capillary forces, resulting in improved flexural strength of the consolidated material (0.123 MPa). Full article
(This article belongs to the Section Construction and Building Materials)
Show Figures

Figure 1

16 pages, 4542 KiB  
Article
Studies of Raman-Scattered Technology on S-Shaped Dinaphtho[2,1-b:2′,1′-f]thieno[3,2-b]thiophene-10 (S-DNTT-10)
by Haobing Wang, Olivier Simonetti, Oumaima Et-Thakafy, Nicolas Bercu, Florence Etienne, Sylvain Potiron, Pierre-Michel Adam and Louis Giraudet
Materials 2025, 18(10), 2389; https://doi.org/10.3390/ma18102389 - 20 May 2025
Viewed by 177
Abstract
S-shaped dinaphtho[2,1-b:2′,1′-f]thieno[3,2-b]thiophene (S-DNTT) molecules have shown promise for applications in organic electronic devices, though their molecular characteristics are not fully understood yet. In this study, we first revealed the material characteristics of S-DNTT-10 by vibrational dynamics using Raman spectroscopy and density functional theory [...] Read more.
S-shaped dinaphtho[2,1-b:2′,1′-f]thieno[3,2-b]thiophene (S-DNTT) molecules have shown promise for applications in organic electronic devices, though their molecular characteristics are not fully understood yet. In this study, we first revealed the material characteristics of S-DNTT-10 by vibrational dynamics using Raman spectroscopy and density functional theory (DFT) simulations, employing the B3LYP functional method and the 6-311G (d, p) basis set. The molecular vibrations identified included C–H bending in alkyl chains and the deformation of S-shaped thiophene rings. In addition, surface-enhanced Raman scattering (SERS) with 785 nm incident light was applied to thermally deposited 25 nm S-DNTT-10 thin films with gold (Au) nanostructures. It showed enhanced Raman signals from the lower S-DNTT-10 layers. The findings significantly contribute to the knowledge of S-DNTT-10 molecular properties and also contribute insights into using this material into organic electronic devices in the future. Full article
(This article belongs to the Section Advanced Materials Characterization)
Show Figures

Figure 1

18 pages, 4781 KiB  
Article
Comprehensive Study on Design Optimization and Retardation Mechanism of SS-GGBS-FA Ternary Geopolymer Mortar
by Chen Jin, Jian Geng and Genjin Liu
Materials 2025, 18(10), 2388; https://doi.org/10.3390/ma18102388 - 20 May 2025
Viewed by 142
Abstract
A ternary geopolymer mortar (TGM) was synthesized using steel slag (SS), granulated blast furnace slag (GGBS), and fly ash (FA) as raw materials. The effect of the SS content (0–60%) and the GGBS/FA mass ratio (5:1 to 1:5) on the TGM’s setting time [...] Read more.
A ternary geopolymer mortar (TGM) was synthesized using steel slag (SS), granulated blast furnace slag (GGBS), and fly ash (FA) as raw materials. The effect of the SS content (0–60%) and the GGBS/FA mass ratio (5:1 to 1:5) on the TGM’s setting time was studied. To address the issue of rapid setting, the impact of different mixing methods ((A) dry mixing, (B) pre-dissolution, and (C) pre-coating) and dosages of BaCl2 on the setting and hardening properties of TGM was further explored. The hydration product evolution and microstructural characteristics were characterized using X-ray diffraction (XRD), scanning electron microscopy (SEM), and energy dispersive spectrometry (EDS), with an in-depth analysis of the retarding mechanism of BaCl2. The results indicate that, as the steel slag content increases, the setting time of TGM significantly shortens. The setting time decreases slightly with an increase in the GGBS/FA mass ratio. The mixing method influences the retarding effect of BaCl2, with the C method showing significant advantages over both the A and B methods. Under the C mixing method, BaCl2 consumes the alkaline components (SiO32−) in the alkaline activator and forms a BaSiO3 coating layer on the precursor surface, which further delays the hydration process of the precursor particles. This study provides a promising approach for the high-value utilization of multi-source solid waste and suggests that future research should focus on large-scale application strategies and long-term performance evaluation to support its practical use in sustainable construction. Full article
Show Figures

Figure 1

19 pages, 4694 KiB  
Article
Application and Empirical Verification of the Archard Model in the Deburring Process
by Karol Falandys, Krzysztof Kurc and Jacek S. Tutak
Materials 2025, 18(10), 2387; https://doi.org/10.3390/ma18102387 - 20 May 2025
Viewed by 145
Abstract
This paper presents a method of numerical simulation, using the finite element method for the brush wear process during the deburring of the edge of the workpiece. The work was carried out in the Ansys Workbench environment in the Ansys Mechanical module. This [...] Read more.
This paper presents a method of numerical simulation, using the finite element method for the brush wear process during the deburring of the edge of the workpiece. The work was carried out in the Ansys Workbench environment in the Ansys Mechanical module. This study reviews the effect of selected parameters of the technological process (rotational speed and depth of tool penetration into the workpiece) on the abrasive wear of the tool. The discussion examines the subject of the 3D or 2D approach in terms of results, quality, and time of computation. A series of numerical analyses (2D) were carried out to investigate the effect of process parameters on the wear rate and, consequently, on the tool life. Obtained results on the quantity of worn material were critically assessed in relation to real-world industrial conditions. The difference between the numerical model and the test performed in the industry environment varied from 3 to 46% and was discussed in this paper. Additionally, to improve the quality of the results in Ansys, an APDL script with adaptative mesh was prepared. The article contains a discussion on the possibility of numerical model development. Full article
Show Figures

Graphical abstract

49 pages, 7310 KiB  
Review
Progress of MXene-Based Materials in the Field of Rechargeable Batteries
by Jianfei Gao, Jing Li, Qian Wang and Cheng Zou
Materials 2025, 18(10), 2386; https://doi.org/10.3390/ma18102386 - 20 May 2025
Viewed by 138
Abstract
With the rapid development of electrical energy storage technologies, traditional battery systems are limited in practical applications by insufficient energy density and short cycle life. This review provides a comprehensive and critical summary of MXene or MXene-based composites as electrode materials for high-performance [...] Read more.
With the rapid development of electrical energy storage technologies, traditional battery systems are limited in practical applications by insufficient energy density and short cycle life. This review provides a comprehensive and critical summary of MXene or MXene-based composites as electrode materials for high-performance energy storage devices. By integrating the synthesis techniques of MXenes that have been studied, this paper systematically illustrates the physicochemical properties, synthesis strategies, and mechanisms of MXenes, and analyzes the bottlenecks in their large-scale preparation. Meanwhile, it collates the latest research achievements of MXenes in the field of metal–ion batteries in recent years, focusing on integrating their latest progress in lithium–ion, sodium–ion, lithium–sulfur, and multivalent ion (Zn2+, Mg2+, Al3+) batteries, and reveals their action mechanisms in different electrode material cases. Combining DFT analysis of the effects of surface functional groups on adsorption energy with experimental studies clarifies the structure–activity relationships of MXene-based composites. However, the development of energy storage electrode materials using MXenes and their hybrid compounds remains in its infancy. Future development directions for MXene-based batteries should focus on understanding and regulating surface chemistry, investigating specific energy storage mechanisms in electrodes, and exploring and developing electrode materials related to bimetallic MXenes. Full article
Show Figures

Graphical abstract

17 pages, 1665 KiB  
Article
Evolution Mechanism of Filtration Characteristics of Cement Grouting Materials in Sandy Medium
by Xiao Feng, Shilei Zhang, Zhenzhong Shi, Qingsong Zhang, Meiling Li, Wenda Yang, Wen Sun and Benao Hou
Materials 2025, 18(10), 2385; https://doi.org/10.3390/ma18102385 - 20 May 2025
Viewed by 127
Abstract
The seepage diffusion of cement grouting materials into a sandy medium is influenced by the skeleton’s adsorption and the pore channels’ tortuosity, resulting in heterogeneous retention of cement particles during migration. This study established a theoretical model for the filtration coefficient based on [...] Read more.
The seepage diffusion of cement grouting materials into a sandy medium is influenced by the skeleton’s adsorption and the pore channels’ tortuosity, resulting in heterogeneous retention of cement particles during migration. This study established a theoretical model for the filtration coefficient based on the mass balance equation and linear filtration law. Grouting tests were conducted to determine the density of the cement slurry at various diffusion positions, and the filtration coefficient was calculated using the theoretical model. Results indicate that the filtration coefficient varies dynamically along the diffusion distance rather than remaining constant. The surface filtration range of Grade 42.5 Portland Cement slurry in sample S1 is approximately 30 cm, with a final diffusion distance of 190 cm. In contrast, the surface filtration ranges for the 800 mesh superfine cement in S2 and the 1250 mesh superfine cement in S3 are less than 10 cm, resulting in final diffusion distances of 69 cm and 87 cm, respectively. This demonstrates that a longer surface filtration range in the sand sample corresponds to a farther final diffusion distance of the slurry. Additionally, a larger ratio of sand pore diameter to cement particle size results in a smaller filtration coefficient and a greater slurry diffusion distance. Under a constant water–cement ratio, smaller cement particle sizes are associated with decreased slurry fluidity, which reduces the diffusion of cement slurry within the sandy medium. The research findings provide valuable insights for designing borehole spacing in grouting treatment for sandy media. Full article
Show Figures

Figure 1

21 pages, 8169 KiB  
Article
In Situ Investigation of the Mechanical Property Anisotropy of TC11 Forgings Through Electron Backscatter Diffraction
by Qineng Li, Ke Li and Wuhua Yuan
Materials 2025, 18(10), 2384; https://doi.org/10.3390/ma18102384 - 20 May 2025
Viewed by 143
Abstract
Electron backscatter diffraction and scanning electron microscopy were performed herein to in situ investigate the influence of texture on the anisotropic deformation mechanism of TC11 forged components. The in situ tensile specimen was cut from the TC11 ring forging, and the tensile force–displacement [...] Read more.
Electron backscatter diffraction and scanning electron microscopy were performed herein to in situ investigate the influence of texture on the anisotropic deformation mechanism of TC11 forged components. The in situ tensile specimen was cut from the TC11 ring forging, and the tensile force–displacement curve was recorded while the slip lines in the specimen surface detected was traced during the in situ tensile test. The tensile results show that the yield and ultimate tensile strengths decreased in the order of transverse-direction (TD) > rolling-direction (RD) > normal-direction (ND) samples. The anisotropy of the tensile strength was related to the differences in the activated slip systems of the ND, TD, and RD samples. The slip lines results show that in the yielding stage, the ND, TD, and RD samples were dominated by Prismatic <a>, Pyramidal <c + a>, and Pyramidal <a> slips, respectively. In order to further analyze the relationship between the slip system and the yield strength, an anisotropy coefficient was determined to evaluate the differences in resistances for different activated slip systems, providing a good explanation of the variations in the tensile strength anisotropy. The ratios of the critical resolved shear stress (CRSS) of the basal, Prismatic <a>, primary Pyramidal <c + a>, and secondary Pyramidal <c + a> slip systems in the α phase were estimated to be 0.93:1:1.18:1.05 based on the type, number, orientation of slip activations, and Schmid factor. Moreover, the Prismatic <a> slips primarily occurred in the axial and radial (ND and RD) samples with [0001] and [1-21-2] textures, whereas the Pyramidal <c + a> slip system was dominant in the TD samples with [112-2] and [101-2] textures. Overall, this research demonstrates that the activation of the α-phase slip depends on the grain orientation, SF, and the CRSS, promoting strong strength anisotropy. Full article
Show Figures

Figure 1

18 pages, 2169 KiB  
Review
Review of Lightweight, High-Temperature Thermal Insulation Materials for Aerospace
by Qi Zhang, Hongyan Huang, Chaoshuai Lei, Yuanyuan Liu and Wenjing Li
Materials 2025, 18(10), 2383; https://doi.org/10.3390/ma18102383 - 20 May 2025
Viewed by 174
Abstract
Lightweight, high-temperature thermal insulation materials play a critical role in aerospace applications, where extreme temperature conditions necessitate lightweight, high-performance solutions. This paper explores advancements in lightweight, high-temperature insulation materials specifically designed for aerospace environments, focusing on innovative flexible ceramic fiber felts, thermal insulation [...] Read more.
Lightweight, high-temperature thermal insulation materials play a critical role in aerospace applications, where extreme temperature conditions necessitate lightweight, high-performance solutions. This paper explores advancements in lightweight, high-temperature insulation materials specifically designed for aerospace environments, focusing on innovative flexible ceramic fiber felts, thermal insulation tiles, nano-insulation materials (aerogels), and multilayer insulations (MLIs). These materials exhibit superior thermal resistance, low density, and durability under dynamic and harsh conditions. Key developments include the integration of nanostructures to enhance thermal conductivity control and improve mechanical stability. This paper also highlights applications in spacecraft thermal protection systems, providing insights into the challenges of future material design strategies. These advancements underscore the growing potential of thermal insulations to improve energy efficiency, safety, and performance in aerospace missions. Full article
Show Figures

Graphical abstract

Previous Issue
Next Issue
Back to TopTop