This paper present a novel investigation of the dechlorination and degradation of chlorotoluron (CHL) a persistent phenylurea herbicide type contaminant by the highly effective advanced reduction process (ARP), based on photocatalytic activation of hydrogen gas (H2) by UV light and palladium on activated carbon (Pd-C) catalyst under aqueous conditions. Importantly, developed system is based on entirely new degradation mechanism which is much more effective comparing to typical UV-based or catalytic hydrogenation processes. The developed process is dedicated to wastewater treatment applications. This approach achieved >99.4% CHL reduction and >94.1% dechlorination at ambient temperature within 10 min. The degradation process followed a pseudo first order kinetics with kobs of 0.1196 min-1. Studies on degradation mechanism revealed contribution of generated hydrogen radicals (H•) and auxiliary role of hydrated electrons (eaq-). The reaction system was found to be very effective also in presence of inorganic anions. Performed studies proved stability of the performance over 5 cycles using same batch of catalyst. This part of the studies confirmed full applicability of the method for industrial practice. Operational costs of the treatment were estimated around 31.42$/m3.

The development of efficient photocatalysts for CO2 reduction is crucial for the development of carbon-neutral energy systems and sustainable production of fuels. In this study, Mo-modified CeO2 nanoparticles were synthesized and immobilized on SiO2-TiO2 porous microspheres (MICROSCAFS (R)) to improve charge separation, light harvesting, and surface reactivity. Structural and physico-chemical characterization confirmed the successful incorporation of Mo species into the CeO2 lattice, leading to enhanced oxygen vacancy formation and improved redox properties. The photocatalysts were evaluated for CO2 photoreduction, where Mo-CeO2 demonstrated the highest CO and CH4 production rates, which can be attributed to modifications in the defect and electronic structure of CeO2 upon Mo doping, enhancing CO2 adsorption and activation of CO2 molecules. The Mo-CeO2@MICROSCAFS (R) composite further enhanced generation and selectivity towards H2 owing to its macroporous architecture and higher surface hydroxyl density, which improved water activation. These findings highlight the synergistic interplay of Mo doping and MICROSCAFS (R) structuring, establishing Mo-CeO2-based materials as promising candidates for sustainable CO2 photoconversion into value-added fuels.

This study investigates the role of defect engineering in enhancing TiO2-based photocatalysts for CO2 photoreduction through a systematically controlled synthesis. In contrast to previous reports focused on Ti3+ doping of commercial TiO2, here we combine sol–gel synthesis with post-synthetic chemical reduction using sodium borohydride (NaBH4) to obtain TiO2 materials with tunable concentrations of surface defects, specifically oxygen vacancies and Ti3+ sites. By varying both the reduction temperature and NaBH4 dosage, we introduce a new level of control over defect formation. The materials were characterized by X-ray diffraction (XRD), Raman spectroscopy, transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), nitrogen physisorption, and photoelectrochemical measurements. Photocatalytic performance was assessed via CO2 photoreduction under UV–vis irradiation. The sample reduced at 350 °C with 1.5 g NaBH4 showed the highest activity and selectivity toward CH4 and CO, clearly surpassing the performance of commercial TiO2 (P25) and a sol–gel reference without chemical reduction (W-TiO₂_350 °C). The improved performance is attributed to a synergistic balance of Ti3+ sites, oxygen vacancies, and surface hydroxyls, which enhance charge separation and CO2 activation. This work introduces new synthesis–structure–activity relationships and demonstrates the potential of defect-tuned TiO2 materials for efficient and selective CO2 valorization.

In this work, a cost-effective method for fabricating silver–platinum nanoalloys through thermally activated dewetting of thin metallic films is demonstrated. Ag and Pt bilayers with a total thickness of 8 nm were deposited using DC magnetron sputtering, followed by annealing at 650 °C under an argon atmosphere. The process induced the transformation of continuous bilayers into isolated nanoislands through solid-state dewetting. Scanning electron microscopy and transmission electron microscopy analyses revealed the formation of well-defined, nearly spherical nanoislands with a homogeneous elemental distribution, as measured by energy dispersive spectroscopy. Additionally, X-ray photoelectron spectroscopy measurements confirmed the coexistence of both metals in metallic states, with a slight Ag deficiency attributed to its higher instability and desorption during the annealing process. Optical measurements revealed the presence of a single resonance peak. The composition-dependent plasmonic resonance band was observed for low Pt contents, while progressively blue-shifting and decreasing in intensity with increasing Pt concentration. This behavior is consistent with the strong d-electron contribution of platinum, which suppresses plasmonic oscillations. The obtained results demonstrate that thermally activated dewetting enables the synthesis of homogeneous Ag–Pt nanoalloys at the nanoscale, both in volume and on the surface of nanostructures, overcoming miscibility limitations of the bulk Ag–Pt system, and provide insight into their structure–property relationships relevant for catalytic and plasmonic applications.

Controlling the oxidation state and chemical environment of photodeposited metal species remains a fundamental challenge in photocatalysis, as these are dictated by complex and poorly understood metal-support interactions. Here, we suggest a general mechanism by which doping of a photocatalyst substrate (anatase {0 0 1} facets) modulates the local chemical potential and oxygen activation pathways, thereby directing the oxidation, coordination and reactivity of photodeposited CuOX clusters. Using shallow donor (Nb5+) and acceptor (Ga3+) species as model systems, a combined DFT, spectroscopy and reactivity analysis reveals that Nb-induced electron-rich environment promote O2 adsorption and O-O dissociation at NbTi-Cu interfacial sites, accelerating Cu+/Cu2+ cycling, while Ga-induced electron withdrawal suppresses O2 dissociation and stabilizes hydrogen peroxide. Further validation confirmed similar effects for Sc3+ and Al3+ as alternative acceptors. As a proof-of-concept we used the 2% Nb-doped material with deposited 0.5% Cu for achieving state-of-the-art 400 nmol min-1 rate of the hydroxyl radicals generation (probed by coumarin in neutral pH) with 0.5 mM PMS assistance. Finally, we presented high quantum efficiencies/relative photonic efficiencies of this material in degradation of selected pollutants: phenol (20/299%), naphthalene (56/706%), EE2 (18/170%) and methomyl (100/1043%).

In situ exsolution has emerged as a powerful strategy for tailoring fuel electrode catalysts in solid oxide fuel cells (SOFCs), yet its integration with reversible exsolution-dissolution processes and its application to symmetricalcapable electrode design remain largely unexplored. Here, we demonstrate controlled exsolution-dissolution in nanofiber double perovskites as a rational route to engineer high-performance SOFC electrodes operable in both symmetrical and anode-supported configurations. Sm0.9Ba0.9Mn1.8-xFexCo0.1Ni0.1O5+delta nanofiber perovskites enable composition-dependent control of nanoparticle evolution. Under reducing conditions, socketed Co-Ni-Fe alloy nanocatalysts exsolve and partially embed into the perovskite lattice, while oxidation induces their transformation into Fe3-x-yNixCoyO4-type hollow core-shell nano-oxides via a Kirkendall-type mechanism. The nanofiber architecture promotes smaller and more densely distributed nanoparticles compared to powders, enhancing catalytic activity and redox stability. The optimized composite electrode delivers a low polarization resistance of 0.046 Omega cm2 at 800 degrees C. Anode-supported cells achieve a peak power density of 1112 mW cm-2 at 850 degrees C and 877 mW cm-2 at 800 degrees C, while symmetrical cells deliver 816 mW cm-2 at 800 degrees C with stable operation. This work establishes controlled exsolution-dissolution as a versatile platform for designing symmetrical-capable high-performance SOFC electrodes and highlights hollow core-shell nanostructure engineering as a powerful strategy for durable solid oxide electrochemical systems.

One of the main sources of secondary microplastics (MPs) in the marine environment is single-use plastic products. However, research on their adsorption capabilities is still limited. In this study, we used a representative set of well-characterized micro-sized fragments, films, and foam to evaluate differences in copper(II) adsorption via a series of batch adsorption experiments. We aimed to understand how the adsorption capacity of Cu(II) differs between a set of secondary MPs in model seawater. We examined the effect of particle size, surface hydrophobicity, and salinity as factors influencing adsorption. The highest adsorption capacity was observed for foam fragments made from a clamshell PS food container followed by a food tray made from PP (591 ± 168 and 353 ± 45 µg/g of MP, respectively). The presence of a higher salinity environment had no negative effect on the adsorption capacity, except that of spherical PS. Our results suggest that the chosen MPs (hard fragments and films) do not have a high ability for Cu(II) adsorption, except for expanded PS and PP films. This study also highlights the difficulties associated with using irregular pieces of post-consumer plastic in model experiments.

This study presents a novel approach for fabricating ZnIn2S4 (ZIS) thin films using pulsed laser deposition (PLD) and evaluates their performance as photoanodes for photoelectrochemical (PEC) water splitting. The ZIS layers, deposited on fluorine-doped tin oxide (FPO) glass, exhibited a smooth and homogeneous morphology, were semi-transparent, and demonstrated photoactivity under visible light. The influence of illumination direction and electrolyte pH on photocurrent generation and stability was investigated. The highest photocurrent value of 2.82 mA cm-2 was achieved in 0.5 M H2SO4 under illumination directed on the photoactive layer, however, the electrode exhibited low stability in this electrolyte. In contrast, alkaline conditions (0.5 M NaOH) provided enhanced stability, with only a 5 % photocurrent decrease after 300 s, as no significant degradation was observed. A three-step degradation mechanism under acidic conditions was proposed, where the oxidation of S2-to Sai-initiated structural breakdown, followed by sulfate dissolution and the leaching of Zn and In. The results underline the role of electrolyte acidity in accelerating the degradation, particularly under prolonged illumination conditions. Future research should focus on enhancing ZIS durability through protective coatings, doping strategies, or modified electrolytes to mitigate degradation while maintaining high PEC performance.

We present a novel approach for simulating thin film (TF) deposition from the gas phase at the atomistic scale, combining molecular dynamics (MD) and time-stamped force-bias Monte Carlo (tfMC). In this approach, MD, with its fine temporal resolution, captures fast events, such as incident atom-substrate collisions, while tfMC simulates slow relaxation processes, enhancing temporal scale coverage. The proposed approach also adequately models deposition conditions, for example, by accounting for realistic energy and angle distributions in the description of the incident flux. To demonstrate its efficacy, we apply it to simulate the physical vapor deposition of a 3 nm Au TF on crystalline Si. We find that the entire deposition process consisted of four distinct stages: (i) the initial degradation of the Si substrate, (ii) formation of a mixed Au-Si interface layer, (iii) nucleation and growth of a polycrystalline Au layer, proceeding in a fashion close to the Frank-van der Merwe mode (layer-by-layer growth), and (iv) postdeposition relaxation of microstructure. The produced TF was comprehensively characterized, revealing that the deposited polycrystalline Au layer contained a considerable number of defects, including dislocations, stacking faults, grain boundaries, and Si impurities. The analysis also showed that in the simulated high-energy deposition the Si substrate was considerably degraded and that the disordered Au-Si layer which formed at the interface resembled the melt-quenched Au82Si18 eutectic. A comparison with an analogous MD simulation revealed that the MD + tfMC approach extended the accessible time scale 5-fold, allowing us to reach the microsecond scale, and yielding a TF with higher crystallinity and better-developed microstructure. The deposition rate used in the MD + tfMC simulation was two to 3 orders of magnitude lower than in other recent, but purely MD, simulations, being significantly closer to experiment.

The aim of this study was to investigate the possibility of Ag nanoparticle crystallization in B2O3–Bi2O3 glass using a heat treatment method and to investigate the possible influence of the obtained nanoparticles on the emission intensity of Eu3+ ions. Borate–bismuth glasses with different B2O3:Bi2O3 molar ratios of 50:50, 60:40 and 70:50 with Ag and Eu3+ ions were successfully synthesized. The structure of the glasses was studied using XRD and FTIR methods. The XRD results exhibited a characteristic amorphous halo, confirming the absence of long-range order in the samples. The glass transition temperatures of various compositions, required to select the annealing temperature, were measured using DTA analysis. The strong maximum in the UV–Vis spectrum of the sample with the highest Bi2O3 content clearly indicated the presence of Ag nanoparticles in the glass. Moreover, a color change was observed for this sample, from slightly yellow to red. The presence of Ag nanoparticles was further confirmed via TEM and XPS studies. However, with a high content of Ag nanoparticles in the matrix, their positive effect on luminescence intensity was not observed. The obtained results show that B2O3–Bi2O3 glass and glass ceramics, with Ag nanoparticles and rare-earth (Re) ions, could be considered as a new phosphor for light-emitting diodes (LEDs).

Based on the developed phosphate glasses P2O5-K2O-Bi2O3-Nb2O5 doped with Eu3+, the influence of AlF3 and KF on the structural and luminescent properties was investigated. For this purpose, three series of glasses containing from 5 to 15 mol% fluorides were synthesized. Two of the series included the KF additive, which was introduced in two ways - proportionally and disproportionately at the expense of the K2O share. The structural characterization (XRD, FTIR) allowed us to determine the evolution of the internal structure of the glasses caused by changes in the type and content of the introduced additives and the presence of the Eu dopant. Similarly, using DSC/DTA, the thermal properties of undoped matrices were defined. The luminescence enhancement caused by the addition of >= 10 mol% fluorides was confirmed by the obtained fluorescence spectra. The presented studies not only expand the state of knowledge about the effects of fluorides on phosphate glasses but also demonstrate the ease of obtaining materials with improved properties suitable for use as phosphor in LEDs.

Lead-free K0.5Bi0.5TiO3 (KBT) ceramics were prepared using a finely tuned convectional solid-state reaction method. Their phase transitions in unpoled and poled states were examined. The temperature-dependent evolution of the reflections sensitive to structural changes and their 2Θ-positions indicated two temperature-driven phase transitions: tetragonal-tetragonal at about 200 °C, and tetragonal-cubic at around 400 °C. These structural transformations are further corroborated by studies examining Raman spectroscopy, dielectric properties, and mechanical properties. It was demonstrated that a prior E-field poling process significantly influences the polar state, causing an increase in the local degree of order, as well as the transformation of the cubic phase into the tetragonal one. This stabilizes and widens the temperature range of the ferroelectric phase. It was found that phase transformations in KBT are accompanied by a softening of the mechanical behavior similarly to improper ferroelastic transformations. The results demonstrate that KBT possesses favorable structural, dielectric, and mechanical characteristics, making it a potential candidate for electronic applications. The present study provides a clear understanding of the multi-scale structural behavior in multi-phase KBT, bridging micro-heterogeneity behaviors and macro-properties, and demonstrates an effective method of tuning the properties of KBTs by E-poling with a low electric field.

Semiconducting Na2O-V2O5-TeO2 glasses with various Na2O contents were melted and subjected to controlled heating to improve conductivity. Topography analysis were performed using confocal microscopy and scanning electron microscopy on both as-quenched and heat-treated samples. X-ray diffraction confirmed the amorphous nature of the samples post-melting, with subsequent heating resulting in the formation of nanocrystallites primarily composed of vanadium ions. The Na2O addition caused progressive depolymerization of the tellurite-vanadate network, as evidenced by IR spectroscopy, although heating exhibited an opposing effect, particularly noticeable in vanadate-related bands. Thermal properties revealing a decrease in the glass transition temperature, crystallization process, and thermal stability with increasing sodium ion concentration. Electrical properties were investigated using impedance spectroscopy, which enabled determination of DC conductivity values, polaron jump energies, and disturbance energies in the samples. The electrical conductivity mechanisms were described as mixed ionic-polaronic, with polaron hopping predominating. Heat treatment significantly enhanced polaron conductivity and altered its nature.

This study investigates the synthesis and characterization of Black TiO2 photocatalyst (TiO2-x) through the sol-gel method combined with NaBH4 reduction at different temperatures (350 degrees C, 500 degrees C, and 650 degrees C). The photocatalytic performance for CO2 reduction was evaluated, revealing that TiO2-x_500 degrees C sample exhibited the highest efficiency. This enhanced performance is mainly attributed to a higher concentration of oxygen vacancies and successful nitrogen doping resulting from ammonia water addition during synthesis. Comprehensive characterization techniques, including Raman spectroscopy, and XPS confirmed the presence of defects and their correlation with increased photocatalytic activity. These findings confirm the importance of defect engineering and doping in optimizing TiO2-based photocatalysts for CO2 photoreduction.

The single crystals of lead-free Na0.5Bi0.5TiO3 were grown using the Czochralski method. The energy gaps determined from X-ray photoelectron spectroscopy (XPS) and optical measurements were approximately 2.92 eV. The current-voltage characteristics, depolarization current, dc (σdc) and ac (σac) electrical conductivity, and Seebeck coefficient of the crystals were investigated. The frequency/temperature-dependent electrical properties were also measured and analyzed through complex impedance spectroscopy. An overlapping reversible insulator-metal transition (resistive switching) on nanoscales, caused by the electric field, was detected. Most of these properties were measured for the first time. The activation energy values determined from the conductivity data, the imaginary part of the electric impedance and the modulus indicate that the relaxation process in the high-temperature range is attributable to both single and double ionized oxygen vacancies, in combination with the hopping of electrons between Ti4+ and Ti3+. P-type electrical conductivity was also found. These discoveries create new possibilities of reducing the electrical conductivity of NBT and improving the process of effectively poling this material. Our results indicate the possibility of tuning the material properties by intentionally creating non-stoichiometry/structural defects (oxygen vacancies, cation excess and cation deficiency).

A simple, cost-effective, one-pot method was proposed to introduce bis-phosphonic groups onto alginic acid and carboxymethyl cellulose (CMC). New derivatives were characterized by means of nuclear magnetic resonance, X-ray photoelectron, and attenuated total reflectance Fourier transform infrared spectroscopy. These analyses confirmed the successful transformation of carboxylic groups present in alginic acid and CMC into bis-phosphonic groups. Additionally, thermogravimetric analysis coupled with differential scanning calorimetry was employed to investigate the thermal properties of the bis-phosphonic derivatives of alginate and CMC. The results clearly demonstrate the char-forming ability of both studied bis-phosphonated polycarbohydrates, suggesting their potential as intumescent materials.

The reduction of lanthanides (Ln3+) incorporated into alkali earth sites in a matrix, , requires the creation of electron donating defects, e.g., and elimination of charge compensation defects, e.g. V′′Me, from the vicinity of the .

In this study, Co-bearing Metal-Organic Frameworks (MOFs) are grown via a facile solvothermal process on the surface of two kinds of conductive substrates - titanium dioxide nanotubes (TiO2NT) and fluorine-doped tin oxide (FTO) glass and tested as electrodes in the electrochemical hydrogen evolution reaction (HER). The materials derived from three organic linkers - terephthalic acid (Co-BDC), 2-aminoterephthalic acid (Co-BDCNH2), and trimesic acid (Co-BTC) are characterized by FTIR, Raman, XRD, SEM-EDS, BET, and XPS. Among the layers on FTO without post-synthesis treatment, Co-BTC shows the highest activity (overpotential of HER 1.72 V vs. Ag/ AgCl/KCl). The effects of substrate change on TiO2NT and annealing of Co-BTC layers in air and argon on their electrocatalytic properties are also studied. Using TiO2 nanotubes as a substrate and annealing the material in air results in a reduction of the hydrogen evolution overpotential to 1.44 V vs. Ag/AgCl/KCl and a significant reduction in the exchange current density.

In this study, we present the crystallographic and magnetic characterization of a new intermetallic compound Sm2PdGe3, which was synthetized by a two stage method employing an eutectic alloy. The investigations carried out exhibited, that Sm2PdGe3 crystallize in AlB2-type structure with lattice parameters a = 4.2189(1) & Aring; and c = 4.1031(2) & Aring;. This compound can be classified as a cluster-glass with a spin freezing temperature T-f = 10.5 K. Furthermore, there were carried out the analysis of the role of the rare earth (RE) elements on the structural parameters of RE2PdGe3 and draw a correlation between the RE radius and the unit cell parameters. We show that a deviation from the ideal 1:3 Pd:Ge ratio is necessary to synthesize RE2PdGe3 with smaller RE elements.

The Au nanostructures have been coated with an ultra-thin films of amorphous aluminium oxide. Optical absorption spectra show the influence of the thickness of Al2O3 on plasmon resonance wavelength. The observed red-shift of the resonance location with the increase of the thickness of the Al2O3 film, can be explained by the change in the dielectric function of this film. It allows control of the optical spectra of the coated particles. In this paper we present a two ways for determinaton of optical paramaters of aluminium oxide ultra-thin films. The first one is based on a ellipsometry method, while in second approach a shift of plasmon resonance is used for computer simulations of films. The experimental data are in agreement with the results of the FDTD calculations, showing the possibility of both determining such a function for ultra-thin layers by the computer simulation method, as well as predicting the value of the dielectric constant depending on the thickness of the layer. The experimental data needed for the simulation was obtained in studies such as XRD, XPS, SEM and HR TEM. The proposed models can help to adjust the coating thickness to the desired plasmon resonance position.