Surface Elemental Composition Research Articles

Biogenic magnetic nanocomposite of hydroxyapatite and dextran: synthesis, characterization, and enhanced removal of 2,4-D from aqueous environment.

In this study, a biogenic magnetic nanocomposite, HAP@DEX@MNP, using hydroxyapatite from eggshell waste and dextran was developed to efficiently remove 2,4-D from aqueous solutions. The magnetic nano biocomposite underwent rigorous characterization using a comprehensive suite of analytical techniques, including FTIR, XRD, FESEM, EDX, TEM, and VSM. FTIR analysis was used to validate the existence of pivotal functional groups, such as phosphate, carbonyl, hydroxyl, and iron oxide. XRD analysis verified both the crystalline nature of hydroxyapatite and the successful integration of dextran and hematite within the composite structure. FESEM and EDX examinations provided valuable insights into the surface morphology and elemental composition. TEM observations elucidated the existence of nano-sized particles underscoring the unique structural characteristics of the nanocomposite. Batch adsorption experiments were conducted under optimized conditions, highlighting the critical role of pH 2 for efficient 2,4-D removal. The mechanisms driving the binding of 2,4-D to HAP@DEX@MNP were found to encompass diverse interactions, encompassing electrostatic forces, hydrogen bonding, π-π interactions, and van der Waals forces. Adsorption isotherm studies revealed both monolayer and multilayer adsorption, with the Langmuir and Freundlich models fitting well, indicating a maximal adsorption capacity of 217.39µg/g at 25°C. Kinetic investigations supported the pseudo-second-order model for efficient adsorption dynamics, and thermodynamic analysis emphasized the versatility of HAP@DEX@MNP across different temperatures. Importantly, the study highlighted the remarkable regenerative capacity of the nanocomposite using a 0.1M NaOH solution, positioning it as an environmentally friendly option for water treatment. In conclusion, HAP@DEX@MNP holds significant potential for diverse applications in addressing global water treatment and environmental challenges.

Synergistic effect of co-sputtered tungsten-titanium nitride as electrode material for efficient hybrid supercapacitors

The dawn of bimetallic transition metal nitrides has attracted considerable interest as battery grade electrode material for potential energy storage applications. In addition, it is essential to investigate binder-free processes to improve the performance of the fabricated electrodes. In this study, binder-free tungsten‑titanium nitrides (W-TiN) are deposited through RF/DC magnetron co-sputtering onto the conducting nickel foam (NF). SEM, EDX and X-ray diffraction are exploited to investigate surface morphology, elemental composition, and structural properties of sputtered materials. The W-TiN electrodes are characterized through electrochemical investigation in half-cell configuration. The tested W-TiN electrode is further utilized with activated carbon (AC) electrode to develop hybrid supercapacitor device W-TiN//AC. The hybrid device revealed a maximum energy density (Es) of 88.8 Wh/kg and power density (Ps) 1700 W /kg. To further understand the mechanism of hybrid devices, the capacitive and diffusive contributions are computed using linear and quadradic models. This study provides a new direction to integrate co-sputtered binder-free electrode materials and devices for large scale production of advanced hybrid energy storage devices.

Humic Acid Derived from Agricultural Biomass Mitigates Alveolar Bone Loss and Modulates Systemic Inflammatory Cytokines in Rats with Periodontitis.

Humic acid (HA) is a bioproduct that can be extracted from different sources and has anti-inflammatory properties that have been little explored in the treatment and prevention of Periodontal Disease (PD). Thus, we aimed to investigate the effects of oral administration of HA on the progression of PD in rats. Twenty-four male Wistar rats were distributed into three experimental groups (Control/ Sham, PD, and PD + HA). HA was administered by gavage (80 mg/kg/day) for 28 days, and PD was induced 14 days after the beginning of treatment. Bone loss, bone topography, and surface elemental composition were analyzed. Circulating IL1-beta, TNF-alpha, and IL-10 levels were evaluated through Enzyme-Linked Immunosorbent Assay (ELISA). The animals treated with HA showed lower bone loss (p < 0.05). Calcium and phosphorus levels on the alveolar bone surface were lower in the PD group (p < 0.05) compared to the control group, whereas the animals treated with HA exhibited attenuation in this loss (p < 0.05). The animals treated with HA showed reduced TNF-alpha, IL1-beta, IL-10, and the TNF-alpha/IL-10 ratio compared to those with PD (p < 0.05). Treatment with HA attenuated the parameters of alveolar bone loss and modulated systemic inflammatory parameters in rats with ligature-induced PD.

Study of surface structure and interfacial effects on optical and magnetic properties of un-doped and Si-doped hematite films

Thermal evaporation technique has been used to synthesize the α-Fe2O3 (hematite) and Si-doped hematite films on three different substrates (SiO2/Si, Al2O3 and quartz). The post-deposition heat treatment at 800 °C has further improved the crystalline nature of the films. Rutherford backscattering spectroscopy has provided information for surface elemental composition and depth profile. Raman spectra have supported the formation of rhombohedral phase and inter-layer diffusion between substrate and films. The x-ray photoelectron spectroscopy has confirmed the mixed-valence oxidation states for Fe ions and +4 state for the Si ions in Si-doped hematite films. The optical reflectance spectra in the UV–Visible region indicated contributions from the films and film-substrate interface. The Si-doping has enhanced soft ferromagnetic properties in the hematite film with noticeable decrease of the magnetic coercivity and increase of the magnetic moment. The films showed blocking of magnetization at lower temperatures, typically below 125 K, and a wide thermomagnetic irreversibility between zero-field cooled and field cooled magnetization curves. The modified surface chemical structure, ferromagnetism and optical properties in the Si doped hematite films promise their potential applications in spintronics.

Eco-friendly synthesis of nanoceria using orange peel extract for electrochemical detection of selective cadmium ions

Contamination of drinking water and food by cadmium ions (Cd2+) is a major threat to human health and environment. Here, we focus on the fabrication of simple, cost effective, eco-friendly synthesis of Cerium oxide nanoparticles (nanoceria) using orange peel extract for selective detection of cadmium (Cd2+) ions. The green synthesized nanoparticles exhibited cubic structure which was confirmed by XRD studies. The FESEM and EDS image confirm the surface morphology and elemental composition of nanoceria. HRTEM possesses the cubic structure with an average particle size of 17 nm. The green synthesized nanoceria shows a strong absorption Raman spectrum at 465 cm−1. Furthermore, the Electrochemical profile of nanoceria was investigated by cyclic voltammetry and electrochemical impedance spectroscopy. The electroactive surface area recorded for CeO2 modified GCE is 13.24 cm2. The nanoceria modified Glassy carbon electrode (GCE) was used for the detection of toxic heavy metal Cd2+ ion with square wave voltammetry. The linear detection range of Cd2+ was from 10 µM to 1000 µM. The fabricated green synthesized CeO2 electrode exhibited a linear behaviour and the detection limit was found to be 0.47 nM exhibited excellent stability. The green synthesized CeO2 can also be used in trace detection of Cd2+ ions in environmental samples. The nanoceria synthesized via orange peel extract has high electrochemical performance would be of great interest for constructing novel sensing platforms for monitoring heavy metal ions (Cd2+) in environment.

Hydrogen generation by hydrolysis of alkaline NaBH4 solution doped with amorphous catalyst Co–Y2O3–B/CNTs

This investigation enhances the catalytic efficiency of Co–B/CNTs for hydrogen production via sodium borohydride hydrolysis by doping with 5%Y2O3. Such doping significantly boosts hydrogen evolution rates, with Co–Y2O3–B/CNTs achieving a production rate of 1083.43 ml g−1·min−1—surpassing Co–B/CNTs by 1.5 times and tripling that of Co–B catalysts. SEM and XRD analyses show Y2O3 doping reduces particle aggregation and maintains the catalyst's amorphous state, thereby increasing the active surface area. Furthermore, XPS analysis demonstrates that introducing yttrium into Co–B/CNTs catalysts improves their surface elemental composition and valence states. This improvement boosts catalyst performance and stability by enhancing electron transfer and particle size optimization. Optimal hydrolysis is achieved at an NaOH concentration of 2.5 mol/L, with higher concentrations diminishing hydrogen production due to increased viscosity from by-product formation. Additionally, Co–Y2O3–B/CNTs catalysts exhibit commendable durability, maintaining more than two-thirds of their initial activity after five reuse cycles, outperforming comparable catalysts to a moderate extent. These findings underscore the beneficial role of Y2O3 in the Co–B/CNTs framework, promoting Y2O3-doped catalysts for their enhanced efficiency, sustainability, and hydrogen production capabilities.

Severe microplastic pollution risks in urban freshwater system post-landfill fire: A case study from Brahmapuram, India

To investigate the escalating issue of microplastic (MP), pollution in urban water bodies, this study focuses on the aftermath of the Brahmapuram landfill fire in Kochi, India, analyzing its impact on MP concentrations in nearby freshwater system. The study conducted sampling sessions at the landfill site immediately before and after the fire. Post-fire, findings demonstrated a substantial increase in MP concentrations in surface waters, with levels rising from an average 25793.33 to 44863.33 particles/m³, featuring a notable presence of larger, predominantly black MPs. Sediment samples showed no significant change in MP count, but there was a significant increase in mass concentration. SEM/EDS analysis revealed changes in surface morphology and elemental composition, suggesting thermal degradation. Risk assessment using the Microplastic Pollution Index (MPI) and Risk Quotient (RQ) methods indicated heightened MP pollution risk in surface water post-fire. Hierarchical cluster analysis revealed the landfill's proximity as a significant factor influencing MP characteristics in the aquatic system. The study highlights the escalated challenge of MP pollution in urban water bodies following environmental disasters like landfill fires, underscoring the urgent need for policy and environmental management strategies.

Novel insights into whey protein peptide-iron chelating agents: Structural characterization, in vitro stability and functional properties

In this study, whey protein iron chelating peptides were obtained by trypsin hydrolysis of whey protein, and the whey protein peptides-iron chelate (WPP-Fe) was prepared. The structural characterization of the whey protein peptides-iron chelate were determined, comprising ultraviolet-visible spectrum, fluorescence spectrum, infrared spectrum, secondary structure content, x-ray diffraction, particle size, zeta potential, microstructure and surface elemental compositions. The results showed that under the conditions of pH 5.0, the mass ratio of whey protein peptides to FeSO4 was 3:1, chelated at 35 °C for 30 min, iron chelating and chelating yield was 85.92% and 77.38% respectively. The content of aspartic acid and glutamic acid were positively correlated with iron chelating ability. The whey protein peptides-iron chelate had good pH, salt concentration and gastrointestinal digestive stability compared to FeCl2, ferrous gluconate and ferrous glycine. Besides, the DPPH eliminate ability and bacteriostatic properties of the whey protein peptides-iron chelate (WPP-Fe) were better than the whey protein peptide (WPP). These findings can be used as a theoretical basis for the development of new peptide iron supplements.

Near-infrared radiation of gold–platinum submicron particle-decorated nonwoven mats enhances wound healing: In vitro and In vivo studies

Because of their biocompatibility and unique optical and electrical properties, Pt nanoparticles (NPs) have been extensively utilized in biomedical applications. However, the use of pure Pt NPs is hindered by the high costs of raw material and absorption at ultraviolet wavelengths. To leverage the benefits of Pt particles while mitigating their drawbacks, we applied electrospinning technology to prepare polyacrylonitrile (PAN) nonwoven mats decorated with gold and platinum submicron particles (Au5Pt3 submicron particle-decorated PAN). We examined the surface morphology, elemental composition, and chemical structure of the resultant Au5Pt3-decorated PAN nonwoven mats by field emission scanning electron microscopy (SEM), energy-dispersive X-ray (EDX) spectroscopy, and EDX elemental mapping. When subjected to near-infrared (NIR) illumination, the Au5Pt3-decorated PAN nonwoven mats showed a more stable temperature rise than pure PAN nonwoven mats or Au PAN nonwoven mats. Inductively coupled plasma spectrometry demonstrated that the Au5Pt3-decorated PAN nonwoven mats can release more Pt ions under NIR illumination, reaching concentrations of up to approximately 8 ppm. The Au5Pt3-decorated PAN nonwoven mats exerted positive effects in a wounded mouse model, with or without NIR irradiation: the films did not cause wound adhesion or fibrosis, and excellent skin tissue healing and collagen regeneration were observed. Moreover, when combined with NIR illumination, the Au5Pt3 submicron particle-decorated PAN nonwoven mats more strongly inhibited the growth of Gram-positive and Gram-negative bacteria and more strongly enhanced blood vessel generation, compared with the same mats in the absence of NIR illumination. Regardless of NIR irradiation, the Au5Pt3 submicron particle-decorated PAN nonwoven mats do not show significant damage to the liver or kidney in mice. Overall, treatment with these Au5Pt3 submicron particle-decorated PAN nonwoven mats does not result in toxicity in mice and exerts a positive effect on wound healing when combined with NIR irradiation, with enhanced angiogenesis and collagen regeneration.

Ag-doped CuO nanoparticles embedded reduced graphene oxide nanocomposite from Punica granatum peel extract and evaluation of their photocatalytic activity and antimicrobial potential

The present study explored Punica granatum peel extract as a reducing and capping agent for synthesis of Ag-doped CuO nanoparticles embedded reduced graphene oxide (rGO) nanocomposite. The crystalline nature of the Ag doped CuO/rGO was identified utilizing X-ray diffraction (XRD) analysis. The surface morphology of Ag doped CuO/rGO was investigated by Scanning electron microscope (SEM) and transmission electron microscope (TEM) analysis. The surface elemental composition of the prepared material was investigated by the Energy dispersive spectra (EDS) analysis. Ag resulted in enhanced absorbance in the visible range as well as a reduction in band gap energy. The catalytic activity of the green synthesized Ag doped CuO/rGO photocataltyst was evaluated in the reduction of organic pollutants such as 4-nitrophenol (4-NP) and methylene blue (MB) in water at mild conditions. The results indicated that the biosynthesized Ag-CuO/rGO composites have very high and effective catalytic activity over MB dye (99.5 %), high rate constant (0.9871 min−1) and long term stability with 60 min irradiation of UV light. In addition, initial process parameters of catalyst dosage and MB concentration, and pH of the solution were also examined. Differential antimicrobial effects of doped and undoped CuO nanoparticles (NPs) against selected strains of bacteria and fungi were confirmed.

Preparation and properties of micro-arc oxidation ceramic coatings using machine vision technology

In this paper, a machine vision system is combined with non-immersion micro-arc oxidation (MAO) technology, using color as a visual feature, and automatically determining the MAO process through a self-developed color image segmentation program for HSV channel. The robotic arm accurately regulates the machining position and duration. Dense ceramic oxide coatings of similar quality to the artificially prepared coatings were successfully prepared on aluminum (Al) surface. The surface morphology and elemental composition of the samples were characterized using scanning electron microscopy (SEM), energy dispersive spectrometry (EDS) and X-ray diffraction (XRD). The performance of the coatings was tested through thickness tests, hardness tests, and roughness tests. The tribological properties were tested by friction experiments, and its corrosion resistance was tested by electrochemical corrosion tests. The results confirm the effectiveness of a machine vision system for MAO process control, which is capable of preparing high-quality coatings comparable to manual operations. This not only solves the need for precise film formation in different application scenarios, but also provides a more efficient, controllable and innovative solution for the MAO process.

Effect of the pyrolysis conditions and type of feedstock on nanobiochars obtained as a result of ball milling

Currently, the production of nanobiochar (n-BC) using ball milling is a promising and cost-effective method. Studies concerning the physicochemical properties of bulk biochar (b-BC) in relation to pyrolysis temperature, various feedstocks or types of carrier gas have been thoroughly investigated. However, there is a lack of information on how the mentioned conditions determine the properties of the obtained n-BCs. In this study, b-BCs produced from different feedstocks (willow (WL), sewage sludge (SSL), rice husk (RH) and oilseed rape (OSR)), temperatures (450–750 °C) and carrier gases (N2 or CO2) were ball-milled to produce n-BCs. The specific surface area (SBET), elemental composition (C, H, N, O), morphology (SEM), functional groups (FT-IR), and crystalline and amorphous nature of the carbon (RAMAN) were determined. The size of n-BCs depended on the feedstock used (particles ranged from 30 to 87.9 nm). The type of feedstock mostly determined the properties of n-BCs. The most visible differences between n-BCs and b-BCs were observed for surface properties and C content. For all n-BCs, an SBET increase was observed after ball milling, which may enhance the adsorption potential of biochar. The most intense SBET changes were noted for WL-derived n-BCs obtained at 450 °C (increase from 7.2 to 146.3 m2/g) and at 750 °C (increase from 3.9 to 160.8 m2/g) and for RH-derived n-BCs produced at 550 °C (increase from 3.7 to 158.6 m2/g). The C content decreased for n-BCs produced from plant biomass (WL, RH and OSR) and increased (from 20 to 28%) for n-BCs derived from sewage sludge (SSL). Other physicochemical properties mainly depended on the feedstock used for biochar production.

Green mechanochemical activation of solid persulfate to remove PAHs in soil: Performance and mechanism

Due to the high biotoxicity and persistence of polycyclic aromatic hydrocarbons (PAHs), the remediation of PAHs-contaminated soil becomes an intractable problem. Persulfate-based advanced oxidation processes are widely used to degrade PAHs in aquatic environment. However, they are not convenient for used in soil due to the heterogeneity and complexity of soil matrix. In this study, a green and convenient ball milling process is introduced to activate persulfate for the remediation of PAHs-contaminated soil. About 82.5% PAHs were removed with 10% wt. Na2S2O8 (PS) addition and ball-milling for 2 h under 500 r/min. The degradation of PAHs is attributed to the attack of radicals (SO4·- and·OH) generated from the activation of PS by mechanochemistry. Moreover, stable Si-O bonds were disrupted during ball-milling process, and formed free electron on the surface of soil particles. This facilitates the electron transfer from oxidants to contaminants. The particle size, surface element composition, functional group, and thermogravimetric analysis confirmed the slight disturbance of ball-milling-assisted PS process on the physical and chemical properties of soil. Therefore, ball-milling assisted PS approach would be a promising technology for the remediation of PAHs-contaminated soil.

Development and Application of a Nano-Gas Sensor for Monitoring and Preservation of Ancient Books in the Library

Monitoring the gas composition in library environments is crucial for the preservation of ancient books. In this study, TiO2 NTs/CNTs composites were synthesized via a hydrothermal method and utilized as nano-gas sensors for NO2 detection. The surface morphology and element composition of the samples were characterized using scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS). Additionally, the gas sensitivity of the prepared TiO2 nanocomposites was evaluated at different temperatures, both with and without ultraviolet light irradiation. The results demonstrate that the synthesized TiO2 NTs/CNTs samples exhibit a large specific surface area due to their titanium dioxide nanotubes (TiO2 NTs) and carbon nanotubes (CNTs) composition. Moreover, these samples display excellent gas sensitivity under ultraviolet light irradiation at temperatures of 120 °C. Compared to uncomposited and non-ultraviolet light irradiated samples, the sensor response rate is significantly improved, enabling effective monitoring of NO2 gas in library environments conducive to preserving ancient books. Overall, our findings highlight that the developed TiO2 NTs/CNTs nano gas sensor holds great potential for monitoring and safeguarding ancient books.

Anti-adhesion study of three-dimensional reconstructed carbon coatings

This research study focuses on the investigation of a three-dimensional reconstructed carbon coating based on stainless steel. The investigation encompasses the assessment of surface structure, elemental composition, cytotoxicity, and impact on wound healing. The findings indicate that the carbon coating possesses an approximate thickness of 700 nm, exhibiting a distinctive porous structure. Moreover, the surface water contact angle measures 97.7°, representing a 48.4° increase compared to uncoated stainless steel. Energy-dispersive spectroscopy (EDS) analysis confirms the uniform distribution of diverse elements on the coating’s surface. Additionally, X-ray photoelectron spectroscopy (XPS) verifies a substantial carbon accumulation. The electrical resistance of the stainless steel remains largely intact after the application of the coating, as demonstrated by the four-probe method. Notably, ex vivo porcine liver tissue cutting experiments using carbon-coated electrosurgical pencil electrodes showed a significant anti-adhesion effect, with a reduction in tissue adhesions of 81.3%. Furthermore, the MTT test indicates no significant cytotoxicity associated with the carbon coating. Rat skin-cutting experiments further validate that the coating does not impede the process of wound healing. Overall, this study successfully validated the desirable properties of stainless steel-based 3D reconstructed carbon coatings, such as enhanced surface properties, improved anti-adhesion efficacy, negligible cytotoxicity, and compatibility with wound healing. These findings are important for advancing medical device technology and improving patient outcomes.

Ultrafast processing of zirconia ceramics by transient and selective laser absorption

Ultrashort-pulse lasers (USPLs) are used in the machining of zirconia ceramics (ZrO2) because of their extremely high peak intensities. However, highly efficient and high precision microprocessing of ZrO2 remains challenging. In this study, we applied a transient and selective laser (TSL) processing technique by combining a USPL and a continuous-wave (CW) laser to realize ultrafast drilling of opaque ZrO2. Ultra-high-efficiency TSL drilling of ZrO2 was achieved with a processing efficiency 1800 times higher than that of USPL drilling. The material removal mechanism, hole formation process, and parameter dependence of TSL drilling were revealed by direct observation of the internal processing phenomenon on a timescale of microseconds. The variations in the processed surface characteristics, including surface morphology, elemental composition, and phase composition, are also presented. Subsequently, the effect of different excited electron regions occurring in the picosecond timescale induced by the USPL on the TSL drilling performance is discussed. Finally, the repeatability and stability of the TSL processing were verified by fabricating microarrays of different sizes. This study will contribute to revealing the ultrafast processing mechanisms of TSL processing in ZrO2 microfabrication. Furthermore, this technique can significantly broaden the applications of ZrO2 in the advanced electronic industry by greatly improving the microprocessing efficiency.

Synthesis and stabilities of Fe, Ni and Zn oxide incorporated colloidal TiO2

Owing to the unique physical and chemical characteristics of nanoparticles (NPs), their use in the manufacturing of commercial products is on the rise. The future will see an increasing quantity of NPs being discharged into our surroundings. This is precisely why it is important to understand their stability under changing conditions. This research examined the role of added Fe (III), Ni (II) and Zn (II) on the formation and stabilities of aqueous colloids of TiO2 particles. To the best of our knowledge, this is the first attempt to investigate the stability of lab synthesized composite NPs. The study confirmed that both the stability and environmental fate of metal oxide and mixed metal oxide NPs depends on the composition of aqueous environment. This can add more to the general understanding of NPs while paving way for exploring the stability and environmental fate of various mixed metal oxide/composites NPs as previous studies explored only commercially prepared plain NPs. TiO2 and TiO2-Fe2O3, TiO2-NiO, and TiO2-ZnO were synthesized following reported methods. Different characterization techniques including transmission electron microscope (TEM), x-rays diffraction (XRD), energy dispersive X-ray (EDX) analysis, and dynamic light scattering (DLS) were used to confirm the surface morphology, phase, elemental composition, and hydrodynamic (Dh) size of synthesized TiO2 particles. As-synthesized TiO2 and its various forms (TiO2-Fe2O3, TiO2-NiO, and TiO2-ZnO) showed rapid aggregation behavior in solutions, which is a sign of less or no threat to human health and the environment. Among the synthesized composites, TiO2-Fe2O3 showed the highest stability across all the methods utilized in this research. For all the approaches employed in dispersing aggregates of TiO2 NPs and their composites in solution, homogenization method displayed the highest efficiency. Moreover, the addition of an electrolyte i.e., KCl into the particle suspensions has affected the ionic strength of these suspensions resulting in an increased aggregation due to the shifting of ions-particles equilibrium. Thus, the formation of composites on TiO2 can govern both the stability and environmental fate of TiO2 particles under various aqueous environments.

Application of Femtosecond Laser Processing Method in the Sustainable Conservation of Stone Cultural Relics: An Example of Green Schist in Wudang Mountain, China

The ancient building complex in Wudang Mountain, China, is known as the “Museum of Ancient Chinese Architectural Accomplishments”. However, the valuable stone components are preserved in open or semi-open environments and environmental factors such as rain seriously threaten its sustainable conservation. In this context, a femtosecond laser processing method has been demonstrated to be able to prepare hierarchical micro-nano structures on the stone surface to regulate its wettability, achieving the purpose of sustainable conservation. In this paper, the processing mechanism and performance of the femtosecond laser on green schist, a local stone material in the Wudang Mountain, are systematically investigated. It is found that green schist, as a typical non-homogeneous material, exhibits significant differences in its absorption of femtosecond laser with different compositions. Among them, quartz, chlorite, and muscovite are the three main compositions, and they are mainly characterized by cold ablation, thermal melting, and expansion under the irradiation of the femtosecond laser (238 fs, 100 kHz, 40 μJ, 33 μm, 500–40,000 pulses), respectively, and it is difficult to achieve a uniform and stable surface structure. Based on this, we prepared grooves with a spacing of 100–400 μm by scanning the femtosecond laser. Through the characterization of surface morphology, elemental composition, and three-dimensional structure, the processing mechanism of the hierarchical micro-nano structures of green schist under the irradiation of the femtosecond laser is comprehensively revealed. Finally, the wettability modulation result of water contact angle up to 147° is achieved by processing the grooves with an optimal spacing of 400 μm. The results of this research are of guiding significance for the sustainable conservation of ancient buildings and cultural relics.

EBSD characterization of graphene nano sheet reinforced Sn–Ag solder alloy composites

This research explores the effects of incorporating Graphene Nano Sheets (GNS) on the microstructural characteristics and mechanical behavior of Sn–Ag solder alloys. The research was driven by the need for environmentally friendly, lead-free solder alloys with enhanced mechanical and thermal properties. The methodology involved incorporating graphene into the Sn–Ag alloy through stir casting, followed by a series of surface preparation techniques. The composite samples were then examined using EBSD to analyze crystallographic orientations and SEM/EDS for surface morphology and elemental composition. XRD provided insights into phase transformations and structural changes. Key findings reveal that the addition of GNS significantly refines the grain structure of the Sn–Ag alloy, leading to a bimodal grain size distribution. This refinement is attributed to the role of GNS as a nucleation site during solidification. Moreover, the study demonstrates a pronounced alteration in the texture of the material, with an increase in low-angle grain boundaries post-GNS addition. This texture change is indicative of enhanced mechanical properties. The results also show a shift in the orientation distribution function (ODF), suggesting a stronger crystallographic orientation due to GNS. These findings suggest that GNS incorporation could lead to improved mechanical and thermal properties in Sn–Ag solder, making them suitable for high-performance electronic applications. The study concludes that GNS not only serves as an effective reinforcement in Sn–Ag solder alloys but also significantly alters their microstructural and textural characteristics, contributing to the alloy's potential application in environmentally conscious electronic manufacturing.

Phase transformation of AB5 to AB2 type phase on substitution of Mn with Zr in TiVCoNi (ZrxMn2-x) (x = 0, 0.3, 0.6, 1.0) high entropy alloys

In this present investigation, we discussed the synthesis, microstructure, and phase transformation from BCC (AB5) to C14 Laves (AB2) phase in TiVCoNi (ZrxMn2-x) (x = 0, 0.3, 0.6, 1.0) high entropy alloys on substituting Mn with Zr. These high entropy alloys were synthesized using a 35 kW radio frequency induction furnace under an argon atmosphere. At x = 0 (i.e. in quinary HEA), the single BCC phase was observed, whereas at x = 1 (i.e. in hexanery HEA), the single C14 Laves phase was found to be stable. The calculations of the thermodynamic parameters were done with the help of Miedema's semi-empirical model and other models available in the literature. TiVCoNi (ZrxMn2-x) high entropy alloys exhibited mixing enthalpy at x = 0, 0.3, 0.6, 1 as −15.6 kJ/mol, −18.1 kJ/mol, −22.8 kJ/mol, −25.3 kJ/mol respectively. The corresponding atomic size mismatch was found to be 10.03%, 11.85%, 10.18%, and 9.86%. It is established that on replacing Mn with Zr, the mixture of the BCC and Laves phase was observed, which was converted into a single C14 intermetallic Laves phase at equiatomic composition, i.e., x = 1. Further, the study of surface morphology and elemental composition of these as-cast high entropy alloys gives us the idea that hardness increases on substitution of Mn in BCC (at x=0) phased-based; TiVCoNi (ZrxMn2-x) (x = 0, 0.3, 0.6, 1.0) high entropy alloys due to the evolution of harder C14 Laves phase.