In this work, we report a novel electrochemical sensor based on a carbon black-incorporated hydrogel-modified screen-printed carbon electrode (CB@hydrogel/ SPCE) for the sensitive and selective detection of L-cysteine (L-Cys). The synergistic combination of conductive carbon black and porous carbon black-alginate/acrylamide hydrogel matrix enhanced the electroactive surface area and facilitated rapid electron transfer, which significantly improved the sensor performance. The CB-hydrogel was characterized by Field Emission Scanning Electron Microscopy (FE-SEM): Fourier transform infrared spectroscopy (FTIR): Cyclic Voltammetry (CV): and Differential Pulse Voltammetry (DPV) techniques. DPV studies revealed the electrochemical oxidation of L-Cys on CB@hydrogel/SPCE followed a diffusion-controlled and quasi-reversible mechanism involving a two-electron transfer process. The sensor exhibited a wide linear range from 5 to 170 µM, with a sensitivity of 1.8 µA mM−1 cm−2, limit of detection (LOD) of 1.26 µM, and limit of quantification (LOQ) of 3.83 µM. The sensor demonstrated an excellent selectivity against common interferents such as ascorbic acid, uric acid, glucose, and dopamine. The practical applicability of the sensor was validated by successful quantification of L-Cys in spiked real samples, including apple juice, orange juice, and yogurt, with high recovery rates and minimal matrix effects. These findings highlight the potential of the CB@hydrogel/SPCE platform for reliable and accurate electrochemical detection of L-Cys in complex food matrices.

Abstract This study examines the high-temperature solid particle erosion (HTSPE) characteristics of the heat-treated Ti–6Al–5Zr–0.5Mo–0.2Si titanium alloy, which is widely used in aerospace applications due to its superior thermal stability and excellent mechanical properties. The erosion behaviour was systematically evaluated using high-temperature solid particle erosion (HTSPE) test rig by varying three key process parameters: specimen temperature (200°C–750°C), erodent velocity (30–100 m/s), and impingement angle (30°, 60°, 90°). A Box-Behnken design (BBD) integrated with response surface methodology (RSM) was employed to formulate a predictive model for the response erosion rate. A second-order polynomial regression model was developed, and statistical tests such as analysis of variance (ANOVA), F-ratio, and coefficient of determination were used to analyse the adequacy of the developed model. Impingement angle emerged as the most significant factor influencing the erosion rate, followed by erodent velocity, and lastly, specimen temperature, which exhibited a relatively moderate effect. The process parameters exhibit a parabolic variation with respect to the erosion rate, with no interaction effect observed. The lowest erosion rate, 0.002217 mg/g, was achieved at a specimen temperature of 304°C, an erodent velocity of 35 m/s, and an impingement angle of 60°. Field emission scanning electron microscopy (FESEM) was employed to examine the surface morphology, revealing characteristic features associated with different erosion mechanisms. At a 90° impingement angle, material degradation was primarily governed by indentation and ploughing, whereas at a 30° angle, cutting and shear deformation were the dominant mechanisms. These results provide valuable insights for optimising operating conditions to enhance erosion resistance in high-temperature aerospace environments.

Freeze-thaw resilience of Shigella flexneri NCCP 10852 in co-culture with Listeria monocytogenes: Implications for biofilm-mediated survival in cold environment.

Exploring complementary analytical techniques for environmental analysis of glacial lakes in the Pyrenees Mountains.

Recently, progress has been made toward understanding the efficiency of polymer composites with natural fibres. With the hope of enhancing the characteristics of polymer composites supplemented with natural fibres in a watery environment, TiO2 nanoparticles have been used to improve their performance in the field. These nanoparticles were filled in luffa-epoxy components at 1, 3, and 5% volume fractions. A combination of çx-ray diffraction and Fourier transform infrared spectroscopy was utilized to conduct the structural examinations. The nanoparticle spread was captured by field emission scanning electron microscopy. Results show that dry nanocomposite's tensile strength and modulus have increased by 74% and, 13%, 137%, and 50% compared with epoxy and 40 vol% luffa-epoxy (E/L) composites, respectively. In wet nanocomposites, maximum reduction in tensile strength and modulus were observed as 27.4% and 16.54%, respectively. The diminished water absorption and thickness swelling percentage of nanocomposites were recorded as 98% and 91.8%, respectively. The onset temperature of these nanocomposites was scattered in the range of 379-393°C, with a maximum char residue of 38%. The increase in the percentage of residue indicates the effectiveness of epoxy's flame retardant, improved thermal stability, diminished water absorption (approximately 2%), and 95% retention of wet composites' tensile properties. These results provided data support for improving the application of nanocomposites in the automobile field and to develop possible patents on the new material development.

A versatile and innovative fluorescent staining reagent for identification of nine types of microplastics: Applications to environmental waters, soil, milk, and biological systems.

A rapid and efficient method for visualisation of microbial biofilms on natural, and industrially- and medically-relevant surfaces, using field emission- scanning electron microscopy.

Resolving Shewanella vesicular nanowire structure during microbial extracellular electron transfer to a poised electrode.

Additive manufacturing (AM) has rapidly evolved due to its design flexibility, ability to enable personalized fabrication, and reduced material waste. In the medical field, fused filament fabrication (FFF) facilitates the production of individualized anatomical models for surgical preparation, education, medical imaging, and calibration. However, the lack of filaments with X-ray attenuation similar to that of biological hard tissues limits their use in radiological imaging. To address this limitation, a radiopaque filament was developed by incorporating gadolinium oxide (Gd2O3) into a biodegradable poly(lactic acid) (PLA) matrix at 1, 3, and 5 wt.%. Thermal and rheological properties were characterized using differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), and melt flow index (MFI) analyses, revealing minor variations that did not affect printability under standard FFF conditions (200 °C nozzle, 60 °C build plate, 0.12 mm layer height). Microstructural analysis via field emission scanning electron microscopy (FESEM), energy-dispersive X-ray spectroscopy (EDX), elemental mapping, and micro-computed tomography (micro-CT) confirmed homogeneous Gd2O3 dispersion without nozzle blockage. Radiopacity was evaluated using gyroid infill cubes, and increasing Gd2O3 content enhanced X-ray attenuation, with 3 wt.% Gd2O3 reaching Hounsfield Unit (HU) values comparable to cortical bone. Finally, the L1 vertebra phantom fabricated from the 3 wt.% Gd2O3 filament exhibited mean HU values of approximately +200 to +250 HU at 50% infill density (trabecular bone region) and around +1000 HU at 100% infill density (cortical bone region), demonstrating the filament’s potential for producing cost-effective, radiopaque, and biodegradable phantoms for computed tomography (CT) imaging.

To extend the service life of sensors in seawater, this work prepared an integrated diffusion-plated Al2O3 film using high-power impulse magnetron sputtering (HiPIMS). The tribological properties of the Al2O3 film in a marine environment were tested using a tribometer. The morphology and evolution of the Al2O3 film before and after the friction tests were investigated by characterization techniques such as field emission scanning electron microscopy (FESEM). The results demonstrate that the Al2O3 film exhibits excellent tribological performance in the marine environment, significantly enhancing the wear resistance of the substrate material. Furthermore, with the protection of the Al2O3 film, the designed pressure sensor achieved high-sensitivity detection of minute operational forces underwater. When applied to a robotic gripper for manipulation tasks, the coated underwater sensor enabled accurate perception of subtle motion states of the grasped objects.

Given the critical role of valve guides in the performance and lifespan of automotive engines, it is crucial to understand and improve their wear resistance. This study focuses on the wear resistance of powder metallurgy valve guides, aiming to systematically analyze the intrinsic relationship between their composition, microstructure, and properties. Three powder metallurgy valve guide samples with different compositions—specifically, a high-MoS2 Fe-C-Mo-Cu-S alloy (1.5 wt.% C, 1.9 wt.% Mo, 1.5 wt.% Cu, 1.4 wt.% S), a low-MoS2 Fe-C-Mo-Cu-S alloy (1.2 wt.% C, 0.3 wt.% Mo, 0.8 wt.% Cu, 0.2 wt.% S), and a Mo-free high-C-Cu Fe-C alloy (1.8 wt.% C, 5 wt.% Cu, 0 wt.% Mo, 0.01 wt.% S)—were studied using field emission scanning electron microscopy, metallographic microscopy, a reciprocating friction testing machine, and a 3D optical profilometer. The results show that the friction coefficient of the high-MoS2 Fe-C-Mo-Cu-S alloy is the highest at 0.5, the low-MoS2 Fe-C-Mo-Cu-S alloy is 0.25, and the Mo-free high-C-Cu Fe-C alloy is the lowest at 0.22. Since the minor wear amount cannot be accurately measured by the gravimetric method, the concave area of the wear-induced average roughness curve is employed to qualitatively indicate the magnitude of material loss: the area of the high-MoS2 Fe-C-Mo-Cu-S alloy is 2964 μm2, the low-MoS2 Fe-C-Mo-Cu-S alloy is 1580 μm2, and the Mo-free high-C-Cu Fe-C alloy is 1502 μm2. The hardness results of the material show that the high-MoS2 Fe-C-Mo-Cu-S alloy reaches 154 HB, the low-MoS2 Fe-C-Mo-Cu-S alloy is 134 HB, and the Mo-free high-C-Cu Fe-C alloy is 145 HB. The porosity results show a difference of about 2% among the three alloys. Based on the microstructure characterization results, it can be concluded that the Mo-free high-C-Cu Fe-C alloy—with high carbon (C) and copper (Cu) content and fine pearlite layers—exhibits excellent wear resistance: high C can improve the hardness of the matrix, while Cu can act as a lubricating phase to enhance the material’s wear resistance. In contrast, although the addition of MoS2 is intended to improve wear resistance, the irregular pearlite generated by MoS2 reduces the wear resistance of the high-MoS2 and low-MoS2 Fe-C-Mo-Cu-S alloys; among them, the high-MoS2 Fe-C-Mo-Cu-S alloy contains a higher amount of MoS2, and large chunks appearing in the tissue easily cause abrasive wear and aggravate material wear during friction. This study provides solid theoretical and practical support for the material selection and performance optimization of powder metallurgy engine valve guides: the identified intrinsic relationship between alloy composition (MoS2, C, and Cu contents), microstructure (pearlite morphology and second-phase distribution), and tribological performance establishes a clear theoretical basis for regulating the wear resistance of such components.

ABSTRACT This study investigates corrosion behavior in seven iron artifacts excavated from the late medieval stratified floodplain site of Kotul, western India. Using x‐ray fluorescence (XRF), x‐ray diffraction (XRD), field emission scanning electron microscopy (FESEM), and energy‐dispersive x‐ray spectroscopy (EDS) analyses, we identify chloride‐induced corrosion and the formation of akaganeite (β‐FeOOH), a phase typically associated with marine environments. Sample LOT‐27 exhibits significant co‐localization of Cl, Pb, and Sn, suggesting micro‐galvanic interactions that destabilize corrosion layers. The mineralogical and textural diversity observed—ranging from acicular and flower‐like forms to plate‐like structures—confirms complex corrosion stratigraphy influenced by episodic wet–dry cycles and soil chemistry. XRD reveals hematite, magnetite, quartz, and calcite as dominant phases, while field emission scanning electron microscopy coupled with energy‐dispersive x‐ray spectroscopy (FESEM‐EDS) highlights heterogeneous rust layering and environmental inclusions. The presence of akaganeite in inland contexts challenges conventional assumptions about its formation, emphasizing the need for targeted conservation protocols including chloride extraction and low‐humidity storage. These results contribute to a broader understanding of inland corrosion dynamics and preservation of archaeological iron.

Incorporating recycled plastics into construction materials offers environmental and economic benefits. This study examined the properties of cementitious composites incorporating recycled polypropylene (PP) powder to evaluate the feasibility of plastics as construction materials. Experimental parameters included PP content and a curing method. Ninety-six specimens were fabricated for compressive strength tests and 48 for flexural strength tests, with six specimens per parameter. The mechanical behavior of the PP cementitious composites was assessed through compressive and flexural strength tests alongside digital image correlation analysis. Field emission scanning electron microscopy (FE-SEM) and mercury intrusion porosimetry (MIP) were used to analyze the pore structure of cementitious composites. Additionally, X-ray diffraction and thermogravimetric analysis examined the thermal and chemical characteristics. Compared with the control specimens, cementitious composites containing 30% PP exhibited approximately 30% reduction in compressive strength but a 28% increase in flexural strength. FE-SEM and MIP results revealed defects that deteriorated the performance of the cementitious composites. However, the compressive strengths exceeded 30 MPa across all the tested parameters, which is satisfactory for construction applications. Furthermore, the addition of PP enhanced flexural strength, providing structural benefits that render it a viable option for sustainable construction materials.

ABSTRACT Sisal and jute woven mat epoxy composites offer uniform fiber distribution and ease of fabrication, with the mat structure significantly enhancing wear resistance. This study compares the adhesive bond strength of these composites using sisal, jute, and hybrid mats joined with single lap, butt, and scarf configurations (ASTM D5868‐01R14) and two epoxy adhesives: LY‐556/HY951 and XIN‐100 IN/XIN‐900. Results demonstrate that enhanced fiber/matrix interfacial bonding increases joint strength, with both fibers exhibiting superior adhesion to XIN‐100 IN/XIN‐900. The hybrid mat achieved the highest tensile strength in both matrices compared to sisal or jute alone. Tensile tests and Field Emission Scanning Electron Microscopy (FE‐SEM) conducted at room temperature revealed the failure mechanisms of the bonded laminates.

The assessment of donor corneas is currently based solely on central endothelial cell (EC) density, which potentially overlooks the transition zone (TZ) regenerative potential. Therefore, the present study characterizes TZ using multimodal imaging techniques to understand its regenerative potential and refine the assessment of donor tissue. Ex vivo donor corneas (n = 41) were examined using phase-contrast microscopy for EC counting and reflectance confocal microscopy (HRTII/RCM) for non-invasive visualization of the TZ. A subset of eight of these corneas underwent ultrastructural analysis using field-emission scanning electron microscopy (SEM) and immunostaining analysis using confocal microscopy. We observed a significant decrease in central EC density (p < 0.001) with increasing storage duration and donor age, while TZ width and TZ surface cell count remained stable. HRTII/RCM and SEM revealed distinct morphological differences (small, polygonal cells, irregular arrangement) in the TZ compared to the peripheral endothelium (PE). Immunostaining revealed elevated expression of progenitor markers (Nestin, ABCG2, SOX2, Lgr5, Vimentin) and reduced expression of endothelial markers (ZO1 and Na/K-ATPase) in the TZ compared to the PE, indicating the presence of a stem cell-like population. These findings suggest that TZ may contribute to endothelial cell regeneration, and HRTII/RCM could serve as a novel tool for TZ evaluation in low EC count donor corneas.

The monitoring of heavy metal ions in environmental and biological systems is of critical importance due to their widespread toxicity and bioaccumulative potential. Among these, ferric ions (Fe³⁺) are essential for human health but toxic in excess, leading to organ damage and oxidative stress. In this study, we present a green, cost-effective, and scalable method for synthesizing carbon quantum dots (CQDs) using Damask rose petals as a natural carbon precursor. These Damask Rose Carbon Quantum Dots (DRCQDs) exhibit excellent optical properties and were explored as a fluorometric sensor for the selective and sensitive detection of Fe³⁺ ions.CQDs were synthesized via a single-step hydrothermal treatment of finely powdered Damask rose petals in deionized water at 175°C for 24 hours. The resulting brown-colored solution indicated successful synthesis and was characterized using UV–Visible spectroscopy, fluorescence spectrophotometry, and field emission scanning electron microscopy (FE-SEM) coupled with energy dispersive spectroscopy (EDS) and elemental mapping. The average size of the CQDs was estimated to be 16.7 nm, with a spherical morphology and good dispersion. Elemental mapping confirmed the presence of carbon and oxygen, with minor contributions from aluminum due to the substrate.The optical properties of the DRCQDs were investigated under UV illumination and fluorescence spectroscopy. The CQDs exhibited strong blue fluorescence, with the emission peak centered at 420 nm when excited at 330 nm. Interestingly, the emission wavelength varied with the excitation wavelength from 280 to 400 nm, indicating excitation-dependent fluorescence—an important characteristic for tunable sensing applications. A concentration-dependent quenching effect was observed, consistent with known photophysical properties of CQDs, where highly concentrated solutions showed reduced fluorescence due to aggregation-induced quenching.The sensing performance of DRCQDs for Fe³⁺ ions was evaluated through fluorescence titration and selectivity experiments. Among various metal ions tested (Cd²⁺, Mg²⁺, Co²⁺, Cu²⁺, Zn²⁺, and Hg²⁺), only Fe³⁺ induced a significant and consistent fluorescence quenching effect, attributed to the strong affinity between Fe³⁺ and surface functional groups (hydroxyl, carboxyl) on the CQDs. The fluorescence quenching mechanism is presumed to be based on non-radiative electron–hole recombination, facilitated by the half-filled 3d orbital of Fe³⁺, which promotes energy transfer and complex formation with CQDs.The limit of detection (LOD) for Fe³⁺ was determined to be 1.11 µM, with a wide linear detection range from 0 to 80 µM and a correlation coefficient of R² = 0.9971, confirming the high sensitivity of DRCQDs for Fe³⁺ ion quantification. The fluorescence intensity decreased progressively with increasing Fe³⁺ concentration, enabling a quantitative relationship for analytical purposes. Optimization of sensing parameters such as pH, CQD concentration, and excitation wavelength was also carried out. DRCQDs displayed stable fluorescence across a wide pH range (4–12), making them suitable for real-sample applications.The selectivity of the DRCQDs toward Fe³⁺ was validated by minimal interference from other commonly co-existing metal ions. Though Cu²⁺ showed moderate quenching (~41.6%), the effect was not comparable to Fe³⁺ (~81% quenching at 50 µM), demonstrating that Fe³⁺ has a unique and stronger binding affinity to the CQD surface functional groups. This specificity is crucial for practical sensing applications in complex matrices.To demonstrate real-world applicability, the sensor was tested in spiked tap water samples using the standard addition method. The recovery values ranged from 93.96% to 104.05%, and relative standard deviation (RSD) values were consistently below 1.4%, confirming the accuracy and precision of the sensor in real conditions.A comparative analysis (Table 1 of the original article) with other green-synthesized CQDs from various natural sources revealed that Damask rose-derived CQDs offer superior sensitivity and selectivity for Fe³⁺ detection. With a lower detection limit and broader linear range, this system performs on par with or better than CQDs derived from blueberry, sugarcane molasses, and citric acid derivatives. Conclusion: This study presents a novel, eco-friendly, and highly effective fluorometric sensor for Fe³⁺ ions based on carbon quantum dots synthesized from Damask rose petals. The DRCQDs demonstrated strong blue fluorescence, excellent selectivity, and high sensitivity for Fe³⁺ ions, with successful application in real water samples. The ease of synthesis, use of natural materials, and impressive sensing performance make DRCQDs a promising candidate for environmental monitoring, water quality assessment, and biosensing applications. Future work could focus on extending the application of DRCQDs to other metal ions, cellular imaging, and nanotherapeutics. Figure 1

The widespread use of nitrofurantoin (NFT), a nitrofuran-based antibiotic commonly prescribed for urinary tract infections (UTIs), has raised concerns due to its potential side effects, including neurological and gastrointestinal toxicity. Monitoring NFT levels in biological fluids such as urine is critical to ensuring patient safety and therapeutic efficacy. In this study, we developed a novel electrochemical sensor based on a nanocomposite of iron oxide (α-Fe₂O₃) and hexagonal boron nitride (h-BN) for the selective and sensitive detection of NFT in human urine samples.The α-Fe₂O₃/h-BN nanocomposite was synthesized via a hydrothermal method, with humic acid serving as a stabilizing agent. The morphology, structure, and composition of the composite were comprehensively characterized using field emission scanning electron microscopy (FE-SEM), energy dispersive X-ray spectroscopy (EDS), elemental mapping (E-Map), X-ray diffraction (XRD), and UV–Visible spectroscopy. The FE-SEM analysis confirmed the formation of spherical α-Fe₂O₃ nanoparticles uniformly anchored on the hexagonal sheets of h-BN. XRD patterns validated the crystalline nature of both components, while UV–vis spectra and Tauc plots revealed a blue shift and bandgap widening in the composite due to quantum confinement effects and increased microstrain, confirming the successful integration of materials.For sensor fabrication, the α-Fe₂O₃/h-BN nanocomposite was drop-cast onto a pre-treated glassy carbon electrode (GCE). The modified GCE demonstrated enhanced electrochemical properties, as evaluated by cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), and amperometry (AMP). The nanocomposite-coated electrode exhibited a significantly improved cathodic peak current and reduced overpotential (−0.49 V) for NFT reduction, indicating superior electrocatalytic activity compared to bare and h-BN-only modified GCEs. EIS analysis further confirmed the enhancement in charge transfer capabilities due to the presence of the nanocomposite.The electrochemical detection of NFT was carried out using amperometry, where the sensor showed two linear response ranges: from 0.025 to 0.45 µM and from 0.70 to 22.95 µM. The sensor achieved an outstanding detection limit of 15 nM and a rapid response time of 2 seconds, with a calculated sensitivity of 2.36 µA µM⁻¹ cm⁻². Scan rate studies revealed that the electrochemical reduction of NFT on the α-Fe₂O₃/h-BN/GCE was diffusion-controlled, as evidenced by the linear relationship between the square root of the scan rate and the peak current.To evaluate its real-world applicability, the sensor was tested for NFT detection in human urine samples using the standard addition method. The recovery rates ranged from 99.47% to 99.93%, and the relative standard deviation (RSD) values were all below 0.5%, confirming excellent accuracy and repeatability. Furthermore, interference studies involving common urine constituents (e.g., urea, uric acid, NaCl, oxalic acid) revealed minimal impact on NFT detection (<4% signal deviation), showcasing the sensor’s high selectivity.The stability and reproducibility of the sensor were also validated. After 50 consecutive CV cycles, the sensor retained approximately 70% of its initial response, indicating commendable operational stability. Repeatability tests conducted with five independently prepared sensors showed a relative standard deviation of 3.72%, reflecting strong fabrication consistency.The high-performance characteristics of this sensor—low detection limit, fast response, high selectivity, and successful detection in real samples—are attributed to the synergistic effect between α-Fe₂O₃ nanoparticles and h-BN nanosheets. The integration of these materials creates a porous and conductive interface that facilitates efficient electron transfer and increases surface area for NFT adsorption. Moreover, including humic acid during synthesis promotes the uniform anchoring of α-Fe₂O₃ on h-BN, enhancing the composite's overall stability and electrocatalytic activity.This work is among the first to employ α-Fe₂O₃/h-BN nanocomposites for the electrochemical detection of nitrofurantoin. The results demonstrate its potential as a robust, cost-effective, and non-invasive diagnostic tool for monitoring antibiotic levels in biological fluids. Beyond NFT detection, the synthesized nanocomposite is promising for broader biosensing, environmental monitoring, and point-of-care diagnostics applications. Keywords: Nitrofurantoin, Electrochemical Sensor, α-Fe₂O₃, Hexagonal Boron Nitride, Human Urine, Amperometry, Nanocomposite, Urinary Tract Infections Figure 1

NiO films were successfully deposited by sol–gel spin coating on Si, glass, and ITO-covered glass substrates. The impact of the film thickness (the different number of layers), annealing temperatures (from 300 to 500 °C), and the substrate type on the crystal structure, film morphology, optical, and vibrational properties was investigated. X-ray diffraction (XRD) revealed a polycrystalline structure and the appearance of the cubic NiO phase. Field Emission Scanning Electron Microscopy (FESEM) was applied to explore the surface morphology of NiO films, deposited on glass and ITO substrates. The oxidation states of Ni were determined by X-ray photoelectron spectroscopy (XPS). The presence of Ni2+ and Ni3+ states was supposed. UV–VIS–NIR spectroscopy revealed that NiO films possessed a high average transparency of up to 74.6% in the visible spectral range when they were deposited on glass substrates, and up to 76.9% for NiO films on ITO substrates. The thermal treatments and the film thickness slightly affected the film transparency in the spectral range of 450–700 nm. The work function (WF) of the samples was determined. This research showed that good properties of sol–gel NiO films can be compared to the properties of those films produced using complicated and expensive techniques.

Ion implantation emerges as a cutting-edge method for defect engineering in crystalline materials, offering unparalleled precision in modulating thermal conductivity. In this study, we employ argon (Ar) ion implantation to manipulate the thermal and phonon transport properties of the thermoelectric material antimony telluride (Sb2Te3). By systematically varying ion implantation doses and energies, we achieve controlled defect structures, characterized comprehensively using advanced techniques such as Transmission Electron Microscopy (TEM), X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), and atomic force microscopy (AFM). The results reveal that defect-induced structural changes, including point defects, dislocations, and amorphous-like regions, significantly suppress thermal conductivity, laying the foundation for enhanced thermoelectric efficiency. This work establishes Ar ion implantation as a scalable, tunable, and transformative approach to defect engineering, unlocking new horizons for thermoelectric materials in energy conversion and advanced thermal management applications.

In the present study we investigated the possibility to use cobalt-phosphorus (CoP) and gold nanoparticles modified cobalt-phosphorus (AuNPs-CoP) coatings as the anode/cathode electrocatalysts for borohydride oxidation-water reduction fuel cells (BOR-HER, BHFCs). CoP coatings were deposited on the copper surface using the electroless metal plating technique, while AuNPs were deposited on the CoP surface by galvanic displacement. The electrochemical behavior of the prepared CoP and AuNPs-CoP catalysts was evaluated in respect to the electrooxidation of sodium borohydride (BOR) in an alkaline media and hydrogen evolution (HER) in acidic media by cyclic voltammetry, linear sweep voltammetry and chrono-techniques. The surface morphology and composition of the samples were characterized using Field Emission Scanning Electron Microscopy (FESEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and inductively coupled plasma optical emission spectroscopy (ICP-OES).It was found that the average size of the Au crystallites deposited by galvanic displacement of CoP adlayer varies from 15 up to 100 nm depending on the immersion time of CoP electrode into the gold-containing solution, while the Au loadings were in the range from 4.21 to 57.6 mg Au cm-2. The data on the BOR in an alkaline medium and HER in an acidic medium on the CoP and AuNPs-CoP catalysts are compared and discussed based on electrochemical data. The performance of the BHFC was evaluated by recording the cell polarization and obtaining the corresponding power density curves at different temperatures. Acknowledgment This research was funded by a grant (No. P-MIP-23-467) from the Research Council of Lithuania.