The main idea of this work is based on the latest achievements in the commercialization of sodium-ion (Na-ion) batteries, which constitute a basis of analysis for military applications as energy storage systems. Technical, engineering, and ecological aspects were analyzed to find the optimal solution for using Na-ion batteries for military purposes. When selecting batteries for military applications, the following criteria are required: (a) they are more durable than standard batteries, (b) resistant to fire, (c) cannot explode, (d) cannot emit heat so as not to reveal their position, (e) equipped with safety elements and protective circuits to ensure safety, and (f) have the highest possible energy density, defined as the ratio of capacity to weight. The advantages and challenges of Na-ion batteries are discussed and compared to typical lithium-ion batteries, and also lithium iron phosphate, Ni-Cd, and Ni-MH batteries. The prospects for expanding the practical applications of Na-ion batteries in the military are presented. The unique properties of Na-ion batteries, such as their lower risk of ignition, more excellent thermal stability, and ability to work in extreme conditions, are essential from the point of view of military operations. Additionally, when considering environmental and logistical aspects, sodium-ion batteries may offer more sustainable and cost-effective solutions for the military. Therefore, this work aims not only to present the technological potential of these systems but also to draw attention to their strategic importance for the future of military operations. Battery discharge can result from leaving current receivers switched on or even from a drop in temperature. The discharge current should not exceed 1/10 of the battery capacity (1C). Discharging below the discharge voltage may result in irreversible damage. Sodium-ion batteries are safer to use than their lithium counterparts and allow for discharge to 0 V, eliminating the possibility of uncontrolled thermal discharge due to a short circuit (explosion, ignition), which is particularly important in the military.

In this paper, four new aromatic imines containing at least one thiazole-based heterocycle were analyzed in detail by UV–Vis spectroscopy, taking into consideration their chemical structures and interactions with PTB7, a known polymeric electron donor widely used in bulk heterojunction organic solar cells. It is demonstrated that the absorption spectra of the investigated active compositions can be modified not only by changing the chemical structure of imine, but also via formulations with PTB7. For all investigated imines and PTB7:imine compositions, calibration curves were obtained in order to find the optimum concentration in the composition with PTB7 for expansion and optimization of absorption spectra. All imines and PTB7:imine compositions were investigated in 1,2-dichlorobenzene by UV–Vis spectroscopy in various concentrations, monitoring the changes in the π–π* and n–π* transitions. With increasing imine concentrations, we did not observe changes in absorption maxima, while with increasing imine concentrations, a hypochromic effect was observed. Finally, we could conclude that all investigated compositions exhibited wide absorptions of up to 800 nm and isosbestic points in the range of 440–540 nm, confirming changes in the macromolecular organization of the tested compounds. The theoretical calculations of their vibration spectra (FTIR) and LUMO–HOMO levels by Density Functional Theory (DFT) methods are also provided. Finally, IR thermal images were measured for organic devices based on imines and the imine:PTB7 composite.

A new unsymmetrical imine with four thiophene rings was synthesized in a one-step reaction, starting from the commercially available and relatively inexpensive reagents. The obtained imine in the form of thin films exhibited photoluminescence properties in the 1.8–2.4 eV energy range and a photoluminescence lifetime of about 0.3 ns. The HOMO and LUMO levels of the imine determined by cyclic voltammetry were at about −5.19 eV and −3.05 eV, respectively. The density functional theory was applied to calculate the geometric and electronic structure of the imine. The UV-Vis spectra showed that the absorption range of the imine overlaps with that of PC₇₀BM, and the absorption peak at the maximum of the imine at 424 nm is located between the two maxima at 404 nm and 461 nm of the fullerene derivative. The electron acceptor and donor activity of the imine was tested in the solar cell architecture: glass/ITO/PEDOT:PSS/active layer/In/Al. The best photovoltaic parameters, with very good reproducibility for each 8 pixels in the cell, were found for the active layer based on ternary mixture PTB7:PC₇₀BM:imine at a weight ratio 8 : 13 : 1, with the power conversion efficiency of about 4%. The external quantum efficiency of devices with the imine was found to be about 40% at 3.3 eV. The thermal imaging together with the recorded current response at increasing potential showed that the presence of imine in the composition has a beneficial impact in terms of current flow stability at temperatures above 200 °C, compared to two component layers with the same imine as an additive.

The nickel(II) complex with a tetradentate Schiff base ligand obtained by condensation of 1,3‐propanediamine with salicylaldehyde (H₂salpn) was studied in a variety of solvents at room temperature. The product, that is, the N′,N′′‐propylenebis(salicylaldiminato)nickel(II) ([Ni(salpn)]) complex, is brown in color in the solid state. The properties of the ligand and complex were characterized by elemental analysis, solubility in common solvents, molar conductivities, and ultraviolet (UV) and visible (Vis) spectroscopy. The [Ni(salpn)] complex is easily soluble in common solvents such as chloroform, methanol, ethanol, dimethyl formamide, dimethyl sulfoxide, acetonitrile, dioxane, acetone, 2‐propanol, and toluene—a necessary condition for observing solvatochromism. The molar conductivity values, equal to 0.0 S mol^‐1 cm² in these solvents, point to a typical non‐electrolyte behavior for this complex. Spectroscopic measurements were used to confirm the square‐planar geometry of the species in solution and to determine the coordination properties of the donor atoms and their bonding abilities (CFM/AOM parameters), as well as trichromaticity coordinate calculations. The results obtained show that the interactions of the metal with the donors depend on the polarity of the solvent.

The main goal of this paper was to study the optical, electrical, and thermal properties of hybrid composites based on biodegradable polymers (L,D-poly(lactic acid), polycaprolactone or Ecoflex^®), single walled carbon nanotubes (SWCN), and 4′-pentyl-4-biphenylcarbonitrile (5CB). The biodegradable polymers’ binary and ternary compositions were analyzed in detail by ultraviolet and visible (UV–Vis) spectroscopy taking into consideration their chemical structure and interactions with 5CB and SWCN. Differential scanning calorimetry (DSC) studies of the created hybrid layers showed thermal stability and changes in glass transition temperature and melting point in comparison to neat polymers, depending on the chemical structure of the polymer used and the type of composition. Morphology of the created layers were investigated by atomic force and polarizing microscopy. The static contact angle measurements of a water drop showed that all of the neat polymer layers were hydrophobic with angle values ranging from 108° to 115°. In addition, in the case of the Ecoflex^® layers, both with and without additives, a rapid sorption of the deposited water drop was observed. Finally, a simple device with poly(ethylene terephthalate) (PET)/indium tin oxide (ITO)/poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS)/poly [[4,8-bis[(2-ethylhexyl)oxy]benzo[1,2-b:4,5-b′]dithiophene-2,6-diyl][3-fluoro-2-[(2-ethylhexyl)carbonyl]thieno[3,4-b]thiophenediyl]] (PTB7): [6,6]-phenyl-C71-butyric acid methyl ester (PC₇₀BM)/Ag/biodegradable polymer:SWCN architecture was constructed and tested using an infrared (IR) thermographic camera to investigate the surface defects on the created hybrid layers. Increasing the SWCN admixture from 0.01 to 0.5% significantly improved the conductivity only in the case of L,D-poly(lactic acid):SWCN (10:0.5), for which above 5 V, a current with a resistance of 3030.7 Ω could be measured. In order to use the created layers as flexible electrodes, the first experiments were carried out with an admixture of SWCN and poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) as conductive compounds.

The main goal of this review paper is to show the advantages and challenges of photovoltaic cells/modules/panels and scintillators towards carbon footprint reduction for ecological safety. Briefly, the various types of solar-driven CO₂ conversion processes are shown as a new concept of CO₂ reduction. The health toxicity and environmental effects of scintillators, along with risks associated with use and disposal, are presented, taking into consideration inorganic and organic materials. Factors affecting the durability and lifespan of scintillators and the carbon footprint of solar cell production are analysed, considering CO₂ emission. Moreover, the technology of recycling photovoltaic modules and scintillators, along with a SWOT analysis of scintillation material toxicity, is presented to find the best solutions for clean technology and ecological safety. Finally, we offer recommendations for the areas where the most significant reductions in CO₂ emissions are expected to be implemented in the future of green energy in industry, including ESG strategies.