This paper explores the environmental sensitivity of monolayer graphene-based sensor devices for use as sensors under controlled humidity conditions using a combination of scanning electron microscopy (SEM), Raman spectroscopy, Fourier transform infrared spectroscopy (FTIR), and Kelvin probe force microscopy (KPFM). The structural and electrical responses of the graphene devices were examined before and after exposure to water vapor. Raman spectroscopy confirmed the presence of minor defects localized near the contacts, while FTIR revealed distinct spectral changes associated with the adsorption of H2O and displacement of preadsorbed CO2. KPFM mapping demonstrated surface potential redistribution and a reduction of the work function, consistent with improved carrier mobility upon water adsorption. Electrical measurements showed resistance variations that diverge from theoretical predictions for pristine graphene, indicating that environmental contaminants strongly influence device behavior. These results highlight the dual role of water as both a contaminant stabilizer and a charge redistribution agent, emphasizing the importance of environmental control for graphene-based sensing applications, or the inclusion of the expectations of the shift of electric properties caused by the environmental contaminants.

This study presents a comprehensive investigation of the electrical, structural, and electrochemical properties of graphite flake (GF)-reinforced epoxy composites for energy storage applications. Epoxy/GF composites with filler loadings of 10, 30, 50, 70, and 80% wt. were fabricated to evaluate the effect of graphite concentration on conductivity, charge storage, and structural integrity. Impedance spectroscopy demonstrated that quantum-mechanical tunneling, consistent with fluctuation-induced tunneling transport, predominates charge transfer over a wide temperature range, ensuring strong electrical performance. The results show that at 10-30% wt.% GFs, incomplete conductive networks and limited electron and ion transport reduce electrochemical performance. At 50-70% wt.% GFs, the composites exhibited the highest specific capacitance and excellent cyclic stability due to the formation of well-connected three-dimensional conductive networks with sufficient porosity for efficient ion diffusion and charge transport. At filler loadings above 70 wt.%, graphite agglomeration, pore blockage, and microstructural defects were observed, resulting in reduced conductivity and capacitance. SEM, FTIR, and XRD analyses confirmed optimal chemical and morphological interactions at moderate filler contents, highlighting structural degradation at excessive loadings. These results indicate that an optimal graphite content of 50-70% by weight balances conductive pathways, mechanical stability, and electrolyte accessibility, providing a blueprint for designing epoxy/graphite composites that are robust and efficient for next-generation energy storage devices.

Polymer films and coatings play an increasingly critical role in extending material functionality across industrial, biomedical, and environmental applications. Recent advances in surface engineering have enabled precise control of interfacial properties, leading to enhanced durability, cleanliness, and protection. This review summarizes state-of-the-art strategies for modifying polymer surfaces, with an emphasis on plasma-based surface modification and plasma-induced polymerization as versatile, solvent-free methods for tailoring wettability, chemical functionality, and adhesion. Furthermore, it examines emerging classes of self-cleaning and self-sterilizing coatings that leverage photocatalytic, hydrophobic, or antimicrobial mechanisms to mitigate contamination, biofouling, and pathogen transmission. Additionally, developments in high-performance barrier films designed to protect food products and electronic devices through improved resistance to gases, moisture, and chemical agents are highlighted. By integrating insights from materials chemistry, surface physics, and nanostructured coating design, this review provides a comprehensive overview of current achievements and future directions in functional polymer films and coatings aimed at anti-pollution, antibacterial, and anti-corrosion performance.

This study focused on the development of a suitable synthetic polymer scaffold for bone tissue engineering applications within the biomedical field. The investigation centered on electrospun polyvinylidene fluoride (PVDF) nanofibers, examining their intrinsic properties and biocompatibility with the human osteosarcoma cell line Saos-2. The influence of oxygen, argon, or combined plasma treatment on the scaffold’s characteristics was explored. A comprehensive design strategy is outlined for the fabrication of a suitable PVDF scaffold, encompassing the optimization of electrospinning parameters with rotating collector and plasma etching conditions to facilitate a subsequent osteoblast cell culture. The proposed methodology involves the fabrication of the PVDF tissue scaffold, followed by a rigorous series of fundamental analyses encompassing the structural integrity, chemical composition, wettability, crystalline phase content, and cell adhesion properties.

Recent advancements in polymer science have catalyzed a transformative shift in biomedical engineering, particularly through the development of biodegradable and smart polymers. This review explores the evolution, functionality, and application of these materials in areas such as tissue scaffolding, cardiovascular occluders, and controlled drug delivery systems. Emphasis is placed on shape-memory polymers (SMPs), conductive polymers, and polymer-based composites that combine tunable degradation, mechanical strength, and bioactivity. The synergy between natural and synthetic polymers—augmented by nanotechnology and additive manufacturing—enables the creation of intelligent scaffolds and implantable devices tailored for specific clinical needs. Key fabrication methods, including electrospinning, freeze-drying, and emulsion-based techniques, are discussed in relation to pore structure and functionalization strategies. Finally, the review highlights emerging trends, including ionic doping, 3D printing, and multifunctional nanocarriers, outlining their roles in the future of regenerative medicine and personalized therapeutics.

Graphite-based microcathodes have shown significant performance when operated as cold field emission electron sources. Specifically mentioned, cathodes that have been prepared from highly ordered pyrolytic graphite and polymer graphite pencil leads. Such cathodes are characterized by low operating voltages, a long lifetime, a cheap fabrication price, and a stable emission current. Recently, it was shown that polymer graphite cold field emission cathodes have a unique quasi-harmonic field emission behavior, where the process included emission of pulses of electrons with relatively higher emission current values. However, this behavior has not been reported for other graphite-based materials. In this paper, we study the effects of the polymer binding agent on the charge carriers' flow through the surface of polymer graphite using Raman-current spectroscopy. The results from polymer graphite were then compared to cathodes prepared from colloidal graphite conductive paint when deposited on a glass substrate. The results showed that the $I(D)/I(G)$ ratio of polymer graphite had a fluctuating behavior, which was not the case for colloidal graphite, which had a more stable structure.

The accelerating global demand for sustainable materials has brought biodegradable polymers to the forefront of scientific and industrial innovation. These polymers, capable of decomposing through biological processes into environmentally benign byproducts, are increasingly seen as viable alternatives to conventional plastics in sectors such as packaging, agriculture, and biomedicine. However, despite significant advancements, the field remains fragmented due to the diversity of raw materials, synthesis methods, degradation mechanisms, and application requirements. This review aims to provide a comprehensive synthesis of the current state of biodegradable polymer development, including their classifications, sources (natural, synthetic, and microbially derived), degradation pathways, material properties, and commercial applications. It highlights critical scientific and technological challenges—such as optimizing degradation rates, ensuring mechanical performance, and scaling up production from renewable feedstocks. By consolidating recent research findings and regulatory considerations, this review serves as a crucial reference point for researchers, material scientists, and policymakers. It strives to bridge knowledge gaps in order to accelerate the deployment of biodegradable polymers as integral components of a circular and low-impact material economy.

This study is concerned with the research and development of nanofibrous hybrid materials functioning as membranes composed of polyvinylidene fluoride (PVDF) polymer and enriched with metal–organic frameworks (MOFs) as dopants for the adsorption and detection of gases, dyes, and heavy metals in wastewater. Several types of nanofiber composites are fabricated by electrostatic spinning. The prepared samples and their chemical, optical, and material properties are analyzed. Subsequently, the preliminary investigation of dye removal is conducted. Accordingly, the design and investigation of these nanofibrous structures may contribute to addressing critical environmental and technological challenges.

The aim of the presented paper is to take a commercially available prefabricated field effect graphene transistor sensor and to expose it to conditions of normal operation, which are different from clean and standardized laboratory conditions The effect of commonly present gases, humidity, light, possible contaminations like carbon and other phenomena have been allowed to interact with the sensor, which was then analyzed by a series of tests. The structure has been observed by Scanning Transmission Electron Microscopy (STEM), which included both High-Angle Annular Dark Field (HAADF) imaging and energy-dispersive X-ray spectroscopy (EDX). This method, together with Raman spectroscopy and secondary Ion Mass Spectroscopy (SIMS), was used to obtain information about chemical composition. Lastly, the electric properties were observed by taking the current-voltage (IV) characteristics as well as spectral density of current noise to observe changes to the sensor operation ability. The obtained data provide insight into the changes in structure, composition and behavior of the carbon sensor under non-laboratory conditions in order to establish the viability of the sensors in question in practical, less than ideal circumstances in contrast to commonly presented information from pristine, uncontaminated device in ideal laboratory conditions.

Conductive polymer thin films have emerged as a versatile class of materials with immense potential in energy storage and conversion technologies due to their unique combination of electrical conductivity, mechanical flexibility, and tunable physicochemical properties. This review comprehensively explores the role of conductive polymer thin films in three critical energy applications: supercapacitors, batteries, and solar cells. The paper examines key polymers such as polyaniline (PANI), polypyrrole (PPy), and poly(3,4-ethylenedioxythiophene) (PEDOT), focusing on their synthesis techniques, structural modifications, and integration strategies to enhance device performance. Recent advances in film fabrication methods, including solution processing, electrochemical deposition, and layer-by-layer assembly, are discussed with regard to achieving optimized morphology, conductivity, and electrochemical stability. Furthermore, the review highlights current challenges such as scalability, long-term durability, and interfacial compatibility, while outlining future directions for the development of high-performance, sustainable energy systems based on conductive polymer thin films.

The absorption coefficient plays an important role in studying and characterizing semiconducting materials. It is an important parameter to study the mechanism of photons absorption within the structure of the studied material. Thus, it helps to study the several types of charge carrier transport along with the energy band structure and its defects. In literature, a formula was reported to precisely calculate the absorption coefficient from raw data of transmittance and reflectance of electromagnetic radiation. However, the reported formula has several issues limiting its validity in the literature. In this paper, we provide a more mathematically accurate form of this equation to precisely obtain the absorption coefficient from the raw data, by considering the total internal reflection at the different interfaces. Moreover, the equation is tested by simulated data and is applied to study the optical characteristics of a single-component epoxy resin from its transmittance and reflectance raw data.

Nitride salts were added to polyvinylidene fluoride fibers and then the fiber mats were prepared by electrospinning. An experimental investigation of the structure was provided by Raman, FTIR, SEM, and XRD. The phase ratio of the polymer was studied both theoretically and experimentally in connection with the addition of the hydrates Mg(NO3)2, Ca(NO3)2, and Zn(NO3)2 salts. The comparison of simulated and experimental data for vibrational spectroscopies is discussed. We provide a comparison of triboelectric, dielectric, and compositional characterization of PVDF fibers doped with three types of nitride hydrates. Doping of PVDF fibers with magnesium nitrate hexahydrate leads to significant improvement of the triboelectric performance.

Polymer graphite electron sources have performed satisfactorily as field emission emitters and scanning tunneling microscopy probes in the past few years. However, the emission process was characterized by limited total emission currents. This paper introduces the elemental, vibrational, electronic structure, and optical analysis of polymer graphite and glass-graphite composite field emission cathodes to study these limitations. Moreover, the field emission characteristics are studied including the changes in the potential energy barrier of the used materials and structures. Among the studied structures, the cathodes prepared from graphite thin films deposited on a micropointed glass substrate (film-GMF) showed superior performance as random field emission arrays. This includes obtaining much higher emission current values approximate to 20 times) and lower threshold voltages approximate to 1/2) compared to the results obtained from polymer graphite samples. The enhancement factor in such emitters is believed to be the three-dimensional honeycomb structure of graphite. Moreover, the study includes applying graphite coatings to tungsten nano-field emission cathodes and scanning tunneling microscopy probes, which improves the performance of such cathodes/probes in both microscopic techniques.

This study investigates the optical properties of yttrium ferrite thin films fabricated via pulse laser deposition. Yttrium orthoferrite, a ferrimagnetic material known for its potential applications in spintronics and photonics, was deposited on single-crystal substrates under controlled conditions to analyze its optical characteristics. The influence of deposition time on the film quality and optical properties was examined. Atomic force microscopy in contact mode revealed surface roughness variations up to 35 nm, indicating the films’ ability to cover substrate defects. Reflectance measurements determined the optical band gap, which decreased from 3.17 eV for thinner films (44 nm) to 2.91 eV for thicker films (93 nm). Forbidden electronic transitions were also observed, attributed to heteroepitaxial growth and phonon interactions. These results demonstrate the effect of film thickness on morphology and optical properties, making YFeO3 films promising for a range of optoelectronic applications.

Hydrogen embrittlement (HE) remains a pressing issue in materials science and engineering, given its significant impact on the structural integrity of metals and alloys. This exhaustive review aims to thoroughly examine HE, covering a range of aspects that collectively enhance our understanding of this intricate phenomenon. It proceeds to investigate the varied effects of hydrogen on metals, illustrating its ability to profoundly alter mechanical properties, thereby increasing vulnerability to fractures and failures. A crucial section of the review delves into how different metals and their alloys exhibit unique responses to hydrogen exposure, shedding light on their distinct behaviors. This knowledge is essential for customizing materials to specific applications and ensuring structural dependability. Additionally, the paper explores a diverse array of models and classifications of HE, offering a structured framework for comprehending its complexities. These models play a crucial role in forecasting, preventing, and mitigating HE across various domains, ranging from industrial settings to critical infrastructure.

This manuscript presents a comprehensive exploration of the band gap structure of (CoCrFeNiMn)3O4 powders through a series of experimental investigations. The combined use of optical techniques and X-ray photoelectron spectroscopy in this study leads to a comprehensive characterization of the band gap structure in (CoCrFeNiMn)3O4 powders. The findings contribute to the understanding of this material’s electronic properties and pave the way for potential applications in electronic and optical devices.

The development of materials with self-healing capabilities has garnered considerable attention due to their potential to enhance the durability and longevity of various engineering and structural applications. In this review, we provide an overview of recent advances in materials with self-healing properties, encompassing polymers, ceramics, metals, and composites. We outline future research directions and potential applications of self-healing materials (SHMs) in diverse fields. This review aims to provide insights into the current state-of-the-art in SHM research and guide future efforts towards the development of innovative and sustainable materials with enhanced self-repair capabilities. Each material type showcases unique self-repair mechanisms tailored to address specific challenges. Furthermore, this review investigates crack healing processes, shedding light on the latest developments in this critical aspect of self-healing materials. Through an extensive exploration of these topics, this review aims to provide a comprehensive understanding of the current landscape and future directions in self-healing materials research.

This study investigates the optical properties of Yttrium Orthoferrite thin films fabricated via plasma laser deposition. Yttrium Orthoferrite, a ferrimagnetic material known for its potential applications in spintronics and photonics, was deposited on single-crystal substrates under controlled conditions to analyze its optical characteristics. The influence of deposition time, on the film quality and optical properties was examined.

Laser-based techniques for the production and modification of HOPG material are highly demanded in the production of functional surface micro/nanostructures required for various applications. A study on laser ablation of the HOPG using picosecond laser under specified laser and scanning parameters in ambient air to generate structured surfaces is reported in this work. The main objective was to establish the effects of laser fluence, scanning speed, hatching spacing, number of scanning passes and the position of the focal plane on the generation of the different types of micro/nanostructures on the HOPG surface after picosecond laser irradiation. The characteristics of the ablated surfaces of the HOPG formed during laser processing have been studied using Raman spectroscopy and scanning electron microscopy (SEM). Analysis of the Raman spectra indicated there are formations of Raman peaks with different sizes and intensities related to structural defects due to laser ablation. The SEM shows the appearances of laser-induced periodic surface structures (LIPSS) and different nano/microstructures after laser ablation depending on different levels of the parameters. The study shows that surface structures formed on the HOPG depend on the interaction of laser and scanning parameters. This work demonstrates that picosecond laser ablation of the HOPG is an important process that could be applied in different application areas such as nano/microstructures synthesis and thin-film deposition.