Marcin Molenda

Conductive carbon layers/Lithium iron-phosphate (CCL/LFP) nanocomposites with varying CCL coating levels, synthesized from two distinct LFP grain morphologies, were tested as carbon black-free cathodes for Li-ion batteries. The physicochemical and electrochemical properties of the composites were investigated, and their performance as electrode materials was systematically compared to that of standard LFP electrodes with carbon black as an additive. The measured specific capacity of the materials showed that CCL/LFP nanocomposites performed similarly to standard LFP with carbon black electrodes at low currents, while showing significant improvements at higher currents. For the 3.5% CCL composites, 1.4-2.3 times the capacity at 10C was observed in comparison to the standard electrodes. Moreover, taking into account the gravimetric and volumetric differences resulting from the elimination of carbon black additive elimination from the electrode composition, the CCL/LFP composites exhibited significantly improved performance and gravimetric and volumetric energy densities. The electrochemical impedance spectroscopy results confirmed the enhanced conductivity as well as an increased stability of the solid electrolyte interphase (SEI) layer for the CCL/LFP composites. The obtained results show the possibility of elimination of cancerous carbon black additives from electrode composition by using CCL/LFP nanocomposites, thus improving the sustainability of Li-ion electrodes simultaneously enhancing their electrochemical performance.

This study presents the synthesis and comprehensive characterization of tin dioxide nanoparticles (SnO₂NPs). SnO₂NPs were obtained using a conventional wet-chemistry route and an environmentally friendly green-chemistry approach employing plant extracts from rooibos leaves (Aspalathus linearis), pomegranate seeds (Punica granatum), and kiwifruit peels (family Actinidiaceae). The thermal stability and decomposition profiles were analyzed by thermogravimetric analysis (TGA), while their structural and physicochemical properties were investigated using X-ray diffraction (XRD), energy-dispersive X-ray spectroscopy (EDS), ultraviolet–visible (UV–Vis) spectroscopy, dynamic light scattering (DLS), Raman spectroscopy, and attenuated total reflectance Fourier-transform infrared (ATR-FTIR) spectroscopy. Transmission electron microscopy (TEM) confirmed the nanoscale morphology and uniformity of the obtained particles. The photocatalytic activity of SnO₂NPs was evaluated via the degradation of methyl orange (MeO) under UV irradiation, revealing that nanoparticles synthesized using rooibos extract exhibited the highest efficiency (68% degradation within 180 min). Furthermore, surface-enhanced Raman scattering (SERS) spectroscopy was employed to study the adsorption behavior of L-phenylalanine (L-Phe) on the SnO₂NP surface. To the best of our knowledge, this is the first report demonstrating the use of pure SnO₂ nanoparticles as SERS substrates for biologically active, low-symmetry molecules. The calculated enhancement factor (EF) reached up to two orders of magnitude (10²), comparable to other transition metal-based nanostructures. These findings highlight the potential of SnO₂NPs as multifunctional materials for biomedical and sensing applications, bridging nanotechnology and regenerative medicine.

This work is devoted to magnesium oxide (MgO) nanoparticles (NPs) for their use as additives for bone implants. Extracts from four different widely used plants, including Aloe vera, Echeveria elegans, Sansevieria trifasciata, and Sedum morganianum, were evaluated for their ability to facilitate the “green synthesis” of MgO nanoparticles. The thermal stability and decomposition behavior of the MgONPs were analyzed by thermogravimetric analysis (TGA). Structure characterization was performed by X-ray diffraction (XRD), energy dispersive X-ray spectroscopy (EDS), ultraviolet-visible spectroscopy (UV-Vis), dynamic light scattering (DLS), and Raman scattering spectroscopy (RS). Morphology was studied by scanning electron microscopy (SEM). The photocatalytic activity of MgO nanoparticles was investigated based on the degradation of methyl orange (MeO) using UV-Vis spectroscopy. Surface-enhanced Raman scattering spectroscopy (SERS) was used to monitor the adsorption of L-phenylalanine (L-Phe) on the surface of MgONPs. The calculated enhancement factor (EF) is up to 10² orders of magnitude for MgO. This is the first work showing the SERS spectra of a chemical compound immobilized on the surface of MgO nanoparticles.

Non-stoichiometric CeO_2−y, especially in the form of nanocrystal aggregates, exhibits exceptional catalytic activity in redox reactions. It significantly improves the activity of transition metals and their oxides dispersed on/or in it, also acting as an oxygen buffer. Particularly, active oxygen species (O₂ⁿ⁻, O⁻) are generated at the M/CeO_2−y nanoparticle interface, as well as in the surface layer of their solid-state solutions M_xCe_1−xO_2−y. The crystal structure of CeO₂, ZrO₂ and (Ce, Zr)O₂ and its defects are discussed in connection with the resulting specific catalytic activity. All the methods (simple precipitation and co-precipitation from mother liquors, sol–gel methods, precipitation from nanoemulsions, hydrothermal and solvothermal techniques, combustion and flame spray pyrolysis, precipitation using molecular and solid-state matrices, 3D printing and mechanochemical methods) used for the synthesis of these nanomaterials are comprehensively reviewed, describing the rules of individual procedures and preparation details. Methods of deposition of metal catalysts and their oxides on CeO₂ nanoparticles, such as impregnation, washcoating and precipitation deposition, were also discussed. This review contains more than 160 references to representative papers wherein the reader can find further details on individual syntheses of effective ceria-based catalysts for redox reactions.

In this work we investigate the electrochemical behavior of bio-derived carbon aerogel/ Li4Ti5O12 composites (CAG/LTO) in Li-ion half cells. The studied CAG/LTO samples were successfully prepared through the gelatinization process of potato starch precursor with pristine LTO material, followed by controlled pyrolysis in an inert gas atmosphere. The obtained composites were examined by elemental analysis (EA), X-ray diffraction (XRD), galvanostatic charge/discharge tests (GCDT), extensive cycling (LT-GCDT) and cyclic voltammetry (CV) methods. The results show, that carbon aerogel compressive matrix significantly improved the electrical conductivity of LTO anode material and was effective only in its composite form. The best electrochemical parameters and overall performance was achieved by 16% CAG/LTO composite. After extensive cycling (1016 charge/discharge cycles under 5C), its discharge capacity was equal to 209 mAh/g, achieving the capacity retention of 106%.

With ever‐increasing energy demand, more efforts are dedicated to designing innovative electrode materials providing higher storage capability and power output. As it has been demonstrated recently, the use of mixed cation–anion redox reactions opens up new possibilities for the significant rise of material's capacity and unusual electrochemical characteristics of lithium‐ion battery electrodes. In this paper, a new type of fast cation‐mediated anionic redox reaction in the 3D spinel structure is presented. Li_0.98K_0.01Mn_1.86Ni_0.11O₄ shows 170% of stoichiometric spinel theoretical capacity without voltage hysteresis or significant capacity and voltage fading attributed to limitations of reversible anionic redox. The authors’ sol–gel‐derived defect spinel structure can deliver 250 mAh g⁻¹ at 1C and retain 64% of this capacity under a high 50C current rate. The observed electrochemical process shows the reversibility unseen before in mixed cation–anion redox cathode materials for Li‐ion systems.

Imigranci zagraniczni stanowią nieodłączny element Polskiej gospodarki, co wzbudza zainteresowania nie tylko polityków, ale również naukowców. Zmiana miejsca stałego zamieszkania wiąże się m.in. z potrzebą adaptacji społecznej oraz znalezienia stabilnego źródła dochodu w nowym kraju pobytu. Imigranci nierzadko korzystają z pomocy i wsparcia sieci migracyjnej, a zachowanie kultury i tradycji stwarza dla cudzoziemców okazje biznesowe. Z uwagi na doskonałą znajomość preferencji potencjalnych konsumentów działalność przybyszy jest skoncentrowana m.in. na rynku etnicznym. W artykule poddano analizie wpływ kapitału społecznego na rozwój przedsiębiorczości etnicznej wśród białoruskich imigrantów w Polsce. Artykuł został oparty na przeglądzie literatury przedmiotu, danych statystycznych uzyskanych w Ministerstwie Rozwoju, Pracy i Technologii oraz pogłębionych wywiadach indywidualnych wśród imigrantów z Białorusi prowadzących działalność gospodarczą na rynku etnicznym w Polsce.

Among all advanced anode materials, graphite is regarded as leading and still-unrivaled. However, in the modern world, graphite-based anodes cannot fully satisfy the customers because of its insufficient value of specific capacity. Other limitations are being nonrenewable, restricted natural graphite resources, or harsh conditions required for artificial graphite production. All things considered, many efforts have been made in the investigation of novel carbonaceous materials with desired properties produced from natural, renewable resources via facile, low-cost, and environmentally friendly methods. In this work, we obtained N-doped, starch-based carbon aerogels using melamine and N₂ pyrolysis as the source of nitrogen. The materials were characterized by X-ray powder diffraction, elemental analysis, X-ray photoelectron spectroscopy, galvanostatic charge–discharge tests, cyclic voltammetry, and electrochemical impedance spectroscopy. Depending on the doping method and the nitrogen amount, synthesized samples achieved different electrochemical behavior. N-doped, bioderived carbons exhibit far better electrochemical properties in comparison with pristine ones. Materials with the optimal amount of nitrogen (such as MCAGPS-N8.0%—carbon aerogel made from potato starch modified with melamine and CAGPS-N1.2%—carbon aerogel made from potato starch modified by N₂ pyrolysis) are also competitive to graphite, especially for high-performance battery applications. N-doping can enhance the efficiency of Li-ion cells mostly by inducing more defects in the carbon matrix, improving the binding ability of Li⁺ and charge-transfer process.