The increasing prevalence of electronic devices and the development of “smart buildings” have intensified the problem of electromagnetic interference (EMI) pollution. Consequently, there is a pressing need for advanced EMI shielding materials. Graphene‐based polymer nanocomposites are exceptionally promising for this role, owing to graphene’s outstanding electrical and structural characteristics. However, the effectiveness of these composites is highly dependent on the quality of the graphene and its dispersion within the polymer matrix. The synthesis method of graphene, therefore, plays a crucial role in determining the final properties of the nanocomposite. In this study, we report the design and characterization of polymer‐based nanocomposite films based on poly(methyl methacrylate) (PMMA) and incorporating different types of graphene, prepared by a solution casting method. Various graphene samples (NG5–NG10) were obtained by molten salt electrolysis performed at different temperatures (330°C–390°C) and voltages (10–15 V), using the nonstationary current regimes. The obtained nanocomposite films were studied with SEM and TEM microscopy, Raman and XRD spectroscopy, and conductivity measurements. PMMA/nanostructured graphene (NG) exhibited structural parameters depending on the used graphene type and synthesis voltage. Also, PMMA/NG nanocomposites demonstrated changes in electrical resistivity response. The incorporation of just 1 wt% of graphene into the PMMA matrix resulted in a dramatic improvement in electrical properties. Specifically, the electrical resistivity was reduced by seven orders of magnitude for neat PMMA versus the PMMA/NG5 nanocomposite. These findings demonstrate that tuning the electrochemical synthesis parameters is a critical strategy for optimizing the properties of graphene and developing effective PMMA‐based nanocomposites for EMI shielding applications.

In this chapter, we will present different methods of synthesis of PANI-based nanocomposites and their applications as bionanosensors, pH, and gas nanosensors. In this chapter, a comparison of various methods of synthesis of PANI-based nanocomposites with carbon nanotubes and graphene, as well as the production of nanosensors based on Screen Printed Electrodes will be given. Parallel, complete electrochemical and physical characterization of SPE-based nanosensor electrodes will be presented. For biosensing applications, various pharmaceutical active components will be reported. For pH testing, results of seawater testing in various parts of Europe (Sardinia, Barcelona, Napoli) will be reported. Gas-sensing analysis was done for SO₄, CO₂, and NH₃ gases.

In recent years, the detection and determination of numerous drugs and pharmaceuticals in various media have become crucial aspects of modern healthcare and environmental management. Among the available sensing techniques, electrochemical methods, particularly those utilising screen-printed electrodes (SPEs) and different portable equipment have emerged as rapid, effective, sensitive, and inexpensive. This study focuses on the detection of the anti-inflammatory drug diclofenac in neutral media. Cyclic voltammetry measurements were conducted to identify diclofenac and determine the kinetics and electrochemical mechanism of its oxidation, along with assessing the surface characteristics of the employed SPEs. Graphene and modified graphene SPEs were explored as nanosensors for this purpose. The surface of the graphene SPE was modified using polyvinylidene fluoride, applied through a drop modification procedure. The morphology of the examined SPEs was observed by means of scanning electron microscope, while the electrolyte (0.1 g of diclofenac per litre of phosphate-buffered solution, pH = 7.4) was analysed using UV-Vis spectroscopy. The results indicate that the studied SPEs exhibit promising potential for the detection of diclofenac.

In the last decade, intensive research has been performed in the field of analytical electrochemistry, seeking designs of electrochemical sensors capable of providing better analytical characteristics in terms of sensitivity, selectivity, reliability, ease of fabrication and use, and low cost, especially for pharmaceutical drug monitoring. Our research has primarily focused on developing screen-printed electrode-based sensors and their application as electrochemical platforms for drug determination and monitoring, specifically emphasizing their suitability for surface modification. A commercial screen-printed graphene electrode was used as the electrochemical sensing component, which was subsequently modified with polymers, such as polyvinylidene fluoride and chitosan. All studied electrodes were tested using a doxorubicin hydrochloride (DOX) solution with a concentration of 0.002 mol L-1 dissolved in 0.1 mol L-1 phosphate-buffered saline at pH 6.7. Cyclic voltammetry was used as an electrochemical characterization technique to gather data on all tested electrodes' electrochemical activity. The morphological characterization of the electrodes was done using scanning electron microscopy. The changes in the electrolyte during the electrochemical measurements were followed through ultraviolet-visible spectroscopy. The modified electrodes demonstrated a favorable electrochemical response to DOX and exhibited higher electrical conductivity than the commercial one. The characterization results indicated that the Ch-modified electrode exhibited excellent electrochemical conductivity and demonstrated strong electrochemical performance. The evaluations of this electrode comprised the definition of the lowest limit of detection and limit of quantification among the tested electrodes, with values of 9.822 and 32.741 µmol L-1, respectively, within a linear concentration range from 1.5 to 7.4 µmol L-1. Additionally, the electrodes showed excellent repeatability, stability, and reproducibility, confirming their suitability for sensitive DOX detection.

In recent decades, due to the rapid development and application of wireless communication, flexible electronics, and smart devices, electromagnetic interference (EMI) and radiation pollution have been intensified, creating an urgent demand for efficient EMI shielding materials. Carbon nanostructures such as graphene and carbon nanotubes are considered promising candidates due to their excellent properties, such as high electrical conductivity, low density, large specific surface area, and flexibility. This work reports our recent results in the design and testing of polymer nanocomposites with irradiated hybrid carbon nanostructure (graphene/multi-walled carbon nanotubes) used as EMI shielding materials. Five representative composites with varying filler loadings (AH of 15% and AM1 of 20 wt%), thicknesses (0.208–0.48 mm), and e-beam irradiation doses (from 50 to 400 kGy) were systematically characterized using SEM, FTIR, TGA/DSC, and vector network analyzer (VNA) measurements in the S-band (2.65–3.90 GHz). The effects of different e-beam irradiation doses and hybrid carbon contents on conductive network construction, interface engineering, and porous or layered structures on EMI shielding performance are discussed. Experimental results show that all studied composites exhibited strong absorption-dominant behavior (SE_A), while the multiple reflection component (SE_M) was found to be negligible. Both filler loading and sample thickness significantly enhanced shielding performance, with a pronounced synergistic interaction observed between these parameters. A quadratic Response Surface Methodology (RSM) model was developed to correlate the total shielding effectiveness (SE_T) with thickness and filler content, yielding high predictive accuracy (R² > 0.96). The model enables efficient optimization of composite design for targeted shielding levels.

Detecting contaminants in aquatic environments, including wastewater and natural water bodies, is essential for safeguarding environmental health and ensuring water quality. Pharmaceuticals, often incompletely metabolised by humans and animals, persist in the environment and pose risks to ecosystems due to their bioactivity and accumulation potential. Water, as a vital resource for all industries, including mineral and metallurgy, faces increasing challenges from pollutants, making advanced detection methods crucial. This study investigates the application of polymer-modified screen-printed graphene electrodes for the sensitive detection of doxorubicin. The use of graphene not only in energy storage devices but also in sensors makes such materials important for a green and sustainable economy. Electrode performance was evaluated at three pH levels, within a linear concentration range from 1.5 to 7.4 µmol L ⁻¹ . The electrodes’ excellent stability and enhanced sensitivity highlight their potential as cost-effective and rapid tools for monitoring pharmaceutical residues in aquatic environments, contributing to pollution management and environmental protection.