This research addresses marine pollution, a critical environmental issue, by developing an innovative solution to overcome the limitations of traditional cleaning methods. Existing techniques are often inefficient due to their complexity, time-intensive processes, specialized personnel requirements, and high costs. This study explores a novel approach: the development of a superhydrophobic coating on copper foams as an efficient alternative for marine depollution.

Various efforts in creating hydrophobic porous materials, such as electrospinning and chemical vapor deposition, have faced challenges like high equipment costs, energy demands, and the use of harmful chemicals. In contrast, this study proposes a cost-effective and simplified method. A superhydrophobic coating was successfully fabricated on copper foams with varying levels of surface roughness through a two-step immersion process in silver nitrate and stearic acid solutions. Importantly, the substrate's surface roughness significantly influenced the growth of silver dendrites and the morphologies of stearic acid, resulting in distinct structural differences between rough and smooth copper foams. This process requires minimal chemicals, simple equipment, and fewer steps, making it a practical and sustainable option.

The hydrophobic coatings achieved exceptional contact angles of 180°, significantly higher than those reported in most studies. The coatings demonstrated remarkable thermal and chemical stability when subjected to different temperatures (100°C and -15°C) and immersion in water and NaCl, HCl, and NaOH solutions, even after a 40 h exposure. The separation efficiency remained consistently above 94% across various pollutants, demonstrating excellent stability and durability regardless of the substrate's surface roughness. The mechanical durability of the modified copper foams was evaluated through dragging tests and exposure to ultrasound, exhibiting promising results.

This study offers a transformative approach to marine depollution, presenting cost-effective and robust solutions that align with existing environmental strategies to protect and restore marine ecosystems.

Organic coatings are among the most effective solutions to enhance the corrosion resistance of metals. Traditionally, solvent-based coatings have been widely used in industrial applications. However, due to environmental regulations, water-based coatings are in demand due to their lower toxicity. One of the main challenges associated with water-based coatings is how to avoid flash rust corrosion on the metal/coating interface. Typically, this phenomenon is mitigated by incorporating additives such as inorganic corrosion inhibitors. An alternative is the novel approach of using phosphate-functionalized waterborne binders, which has only been explored on mild steel [1].

In the present work, a waterborne binder (consisting of methyl methacrylate (MMA) and butyl acrylate (BA)) was obtained using a polymerizable phosphate-based surfactant and applied on AZ31B magnesium alloy. Different surface pretreatments were used to explore the adhesion and corrosion performance: a) mechanical grinding, b) chemical cleaning, c) zirconium conversion coating (ZrCC), and d) layered double hydroxides (LDHs). The coated samples were cured in a climatic chamber at 23ºC for 24 hours under 60% of relative humidity.

This study included sample characterization in terms of morphology and composition through SEM-EDX and the evaluation of corrosion protection using EIS in a 3.5 wt. % NaCl solution. Additionally, water contact angle measurements and roughness parameters were evaluated.

Polydopamine (PDA) has the rare ability to attach to surfaces traditionally resistant to adhesion, making it a promising candidate for use as a coating. Membranes approximately 20 nm thick PDA were synthesized using cyclical voltammetry electropolymerization and used to produce four examined samples, comprising subsequently higher numbers of PDA stacked layers (from 1 to 4). The stacking of the membranes resulted in a few layered membranes with thicknesses of approximately 20-60 nm. Brillouin light scattering spectroscopy was utilized to investigate the samples' Young moduli and residual stress, determining their mechanical properties through the dispersion of GHz acoustic phonons. The samples exhibited substantial magnitudes of Young modulus, higher than for classical polymers, with the higher values retained in multilayer samples.
The freestanding PDA membranes' responses to varying concentrations of water vapor in the air wereobserved under an optical microscope for all samples. The experiments showed a reversible wrinkling/flattening of the membranes at different relative humidity values. A similar response to laser light, attributed to heat-induced water desorption, was investigated by a home-built setup that allowed for stroboscopic imaging of the membrane morphology with temporal resolution. The process was characterized by relaxation times, attributed to parts of the experiment when the laser light was turned on (flat) and off (wrinkled). The obtained actuation times indicate that the ultrathin membranes react to red laser light in millisecond timeframes, with the multilayer samples having longer relaxation times that remained within the same order of magnitude.

Acknowledgments
Z. K., A. K., M. P., and B. G. acknowledge the National Science Centre of Poland (NCN) for the OPUS grant UMO-2021/41/B/ST5/03038.

References
A. Krysztofik, M. Warżajtis, M. Pochylski, M. Boecker, J. Yu, T. Marchesi D’Alvise, P. Puła, P. W. Majewski, Ch. V. Synatschke, T. Weil and B. Graczykowski, Multi-responsive poly-catecholamine nanomembranes, Nanoscale 16, 16227-16237 (2024), https://doi.org/10.1039/D4NR01050G

Transition-metal borides have exceptional mechanical properties, such as high hardness and fracture toughness. They also have high thermal and chemical stability. Silver, on the other hand, is an attractive material for antibacterial applications due to its biological properties. Combining these materials can make it possible to produce super-hard coatings with antibacterial properties that are also wear-resistant, even under extreme temperature conditions.

In this work, Ag/W_0.84Ti_0.16B_2.5 nanocomposite layers were deposited,comparing their properties with a film made of pure silver. The silver film was produced by pulsed laser deposition (PLD), while the titanium-doped tungsten boride layer was synthesized by high-power pulsed magnetron sputtering (HiPIMS). The structure and chemical composition of the films were characterized by scanning electron microscopy (SEM) and X-ray energy spectroscopy (EDS). The silver particles were uniformly covered with a coating of borides. The surface roughness of the composite was about 100 nm (Ra) and was much higher than the roughness of the layer consisting only of metal borides.

Mechanical properties such as hardness were tested using The Micro Combi Tester MCT3, while wear resistance was verified by abrasion under a reciprocating motion. The silver layer can favorably affect mechanical properties by improving the material's ductility and tribological properties, at the expense of lowering hardness. Biological tests were carried out in a liquid suspension of Staphylococcus Aureus bacteria (a Gram-positive bacterium). Incubation was carried out for 20 hours in a greenhouse at 37°C. Unfortunately, from the studies so far, the composite has not been found to show antibacterial properties in the classic suspension test.

In the pursuit of advanced materials with exceptional properties, tungsten borides have attracted significant attention due to their remarkable hardness, thermal stability, and wear resistance. The crystallographic structure of such materials plays a pivotal role in determining their physical, mechanical, and thermal characteristics. Among these, aluminum-doped tungsten borides (W_1-xAl_xB_2-z) stand out, offering excellent mechanical and thermal properties. These materials show great promise for applications as protective coatings capable of maintaining stability at high temperatures.

To achieve the desired material structure, an innovative magnetron deposition method was employed, combining direct-current magnetron sputtering (DC) and High-Power Impulse Magnetron Sputtering (HiPIMS) techniques. The layer was deposited using two targets: AlB₂ (DC) and WB_2.5 (HiPIMS). An original method involving mass measurements and microscopic observations was applied to determine the density, which was subsequently used to calculate the thermal conductivity. The measured thermal conductivity values (5–8 W/(mK)) classify these materials as thermoelectric. Mechanical testing revealed very high hardness (~30 GPa for doping below 10% atomic aluminum) and a favorable plasticity index (H/E*). As aluminum content increased in W_1-xAl_xB_2-z layers, a slight reduction in density and hardness was observed, along with an increase in thermal conductivity.

Experimental results were compared with theoretical values obtained via DFT calculations. All W_1-xAl_xB_2-z structures analyzed through DFT were found to be mechanically and thermally stable. The experimentally determined hardness values exceeded those predicted by DFT, underscoring the significant influence of aluminum doping.

This study highlights how deposition processes affect crystallinity, texture, and microstructural features, which in turn influence the material's mechanical and thermal properties. Optimization of deposition conditions and doping strategies enabled the development of W_1-xAl_xB_2-z—a promising material with potential industrial applications.

Funding This work was funded by the National Science Centre (NCN, Poland), Project number: 2022/47/B/ST8/01296

Niobium pentoxide (Nb₂O₅ or niobia) exhibits several key properties that make it an excellent optical material. These include exceptional stability, resistance to acidic and basic environments, high optical transmission and refractive index, and minimal light scattering, which further enhance its performance in optical applications. Among the various methods for depositing Nb₂O₅ thin films, sol–gel stands out as a particularly promising approach due to its versatility, scalability, and the ability to precisely tailor material properties for a broad range of applications.

In the current study single- and multi-layered niobia coatings were prepared by spin-coating a niobium sol, which was synthesized using niobium chloride as the precursor and ethanol and water as solvents, followed by annealing at 320^oC to form the niobia film. Doped niobia films were prepared by incorporating commercially available SiO₂ (Ludox) and Au nanoparticles (NPs) into the sol before spin-coating of the films. After annealing the silica-doped films, they were subjected to chemical etching for varying durations to remove the silica phase. This process generated porosity within the films, which in turn enabled the tailoring of both their optical and sensing properties.

The morphology of the films was investigated using transmission electron microscopy (TEM). The optical parameters and film thicknesses were determined by nonlinear curve fitting of the reflection spectra, and the results were cross-validated through additional ellipsometric measurements. Effective medium approximation was used to assess the degree of porosity. The sensing properties of the films were evaluated by using both quartz crystal microbalance (QCM) and optical reflectance spectra measurements, recorded prior to and during exposure to the analyte (acetone vapors).

The study demonstrated that silica NPs enhanced the porosity of the niobia coatings, resulting in vapor-sensitive films with tunable optical and sensing properties. The gold NP doping further improved the sensing performance of the studied films.

In response to the growing challenges of global warming, one of the key phenomena affecting thermal comfort and energy efficiency in cities is the Urban Heat Island (UHI) effect. This refers to higher temperatures in urban areas compared to rural surroundings, caused by building materials like concrete and asphalt that absorb and store heat. In cities with dense buildings and limited green space, there is increased demand for air conditioning, leading to higher energy costs and greater air pollution. Mitigating the UHI effect is thus essential for sustainable urban development.

Roof surfaces, highly exposed to solar radiation, are among the main contributors to heat accumulation. Applying appropriate thermal insulation coatings can significantly improve building energy efficiency. Developing coatings with high Total Solar Reflectance (TSR) can reduce roof temperatures and decrease air conditioning demand, addressing rising energy costs and climate change.

This study aimed to develop dark-colored, multifunctional roof coatings combining corrosion resistance and heat-reduction properties. Direct-to-metal (DTM) coatings, which eliminate the need for an anti-corrosion primer, simplify application and reduce painting time. These formulations incorporated near-infrared (NIR) reflective inorganic pigments that reflect solar radiation in the NIR spectrum, improving thermal performance.

The coatings underwent extensive testing, including adhesion, impact resistance, flexibility, and accelerated aging in salt spray, humidity, and UV chambers. Optical and thermal properties were assessed with UV/VIS/NIR spectrophotometry, and emittance was measured with Total Hemispherical Emittance Measurements.

The coatings demonstrated excellent adhesion and corrosion resistance, with heat-reflective NIR pigments reducing substrate temperature even in dark-gray colors. These results highlight the coatings' effectiveness in mitigating the UHI effect and improving building energy efficiency.

Acknowledgments
This work was financially supported by the Łukasiewicz Research Network Centre (Poland) – grant number: 1/Ł-IMPiB/CŁ/2021

Coatings are undeniable cornerstones of the industry. This technology serves a variety of different purposes, ranging from functional coatings to protective and/or decorative ones. Indeed, a plethora of coating deposition techniques may be described, specifically low-cost, resourceful and practical ones like electrodeposition, that also benefit from its scale-up potential and production feasibility. Electrodeposition techniques are regularly under scrutiny for environmental reasons, yet their relevance and pertinence continue to endure. In this context, numerous efforts are being made to simplify electrolytes, which might influence the nature of chemical waste and the complexity of subsequent treatments. In this study, electrolytes were composed of a limited number of compounds. In line with this, replacing the common but challenging chromium-based electrolytes was also under consideration, with strong alternatives like nickel-based ones emerging. Therefore, the main target of the present work was the achievement of electrodeposited double-layered nickel coatings, specifically dull-nickel pre-coatings followed by black nickel coatings, deposited onto steel substrates. This study highlighted colour quality and decorative potential, as well as the possible enhancement of mechanical properties, such as the coefficient of friction. Additionally, the effect of substrate immersion in HCl for surface activation was also evaluated and adjusted. As a result, the pre-coating characterisation was established. The Scanning Electron Microscope (SEM) analysis unveiled a homogeneous surface and a medium superficial feature of 2.56 μm. As well, the Energy-Dispersive X-ray Spectroscopy (EDS) and X-ray Diffraction (XRD) investigations disclosed the high content of Ni and its crystallinity, respectively. As for the black coatings, the XRD analysis confirmed an amorphous structure. In particular, sample BL10, which corresponds to the black nickel coating deposited for 10 minutes, demonstrated optimal outcomes in terms of colour and roughness, achieving the lowest brightness (L*) value and the least heterogeneous roughness.

Anodic titania nanotubes are characterized by their high degree of vertical alignment, resulting in structures with exceptional surface area, physical, and electrochemical properties. However, their intrinsic wide band gap (ca. 3.2 eV for anatase form) limits their absorption to the UV spectrum, necessitating strategies such as doping and plasmonic decoration to extend their activity into the visible range. Additionally, the semitransparency of these structures can be leveraged to enhance light management and integration into optoelectronic and solar-energy-harvesting devices.

Gold nanoparticles decorated anodic titania nanotubes, exhibiting localized surface plasmon resonance, can potentially improve photocatalytic activity, visible-light absorption, nonlinear optical behavior, and the efficiency of solar energy and photonic devices. These materials can be synthesized through various approaches, including laser-treated titania nanotubes coated with a gold thin film or the laser treatment of oxide nanotubes formed from TiAu homogeneously co-sputtered alloys. However, laser processing often results in non-uniform gold nanoparticle distribution, predominantly on the nanotube surface area, leading to issues like melting, agglomeration, or polydispersity. To address these challenges, we have developed semitransparent anodic nanotubes embedded with gold nanoparticles. These structures were fabricated by anodizing a multilayered film stack composed of alternating Ti-sputtered layers and TiAu co-sputtered layers. SEM analysis revealed well-formed, uniformly distributed nanotubes and the Raman spectra confirmed the presence of the anatase phase in the prepared materials, with up to 7 % of Au content. The UV–vis spectra also revealed a redshift of the absorption band beyond 400 nm, and energy band-gap reduction was observed compared to the bare titania material. Furthermore, the samples exhibited superior anodic current densities, particularly favoring oxygen evolution reactions, reaching up to 2.7 mAcm^-2 for the sample with 5 % Au content. These results underscore the potential of such gold nanoparticle-embedded nanotubular architectures for advanced photoelectrochemical applications.

The 2,5-diformylfuran (DFF) is a significant biomass derivative that is employed in a variety of industries. One approach is to synthesize it by an oxidation process of 5-hydroxymethylfurfural (HMF). The challenges in DFF manufacture come from the necessity for extreme conditions, the overoxidation issue, and the limitations of noble materials employed in neutral or acidic environments. By using mild alkaline as an electrolyte, DFF can be produced electrochemically alongside hydrogen gas generation, eliminating extreme conditions and allowing for the study of a wide range of transition metals. Moreover, the performance of bimetallic electrocatalysts has been studied, and it has been found to be more active in many kinds of processes, particularly Layered Double Hydroxides (LDHs). Electrodeposition, once widely chosen among various LDH production methods, is preferred for producing controlled and uniform thin layers. This work examines the electrocatalytic properties of NiCo-LDH and NiFe-LDH in the production of DFF. Cobalt, which has a high adsorption characteristic, is compared to iron, which has a weak adsorption characteristic towards HMF. This study demonstrates that NiCo-LDH has a higher activity but lower DFF selectivity compared to NiFe-LDH for the same amount of passed charge. Strong adsorption promotes reactant activation and reduces the energy barrier while reducing DFF selectivity due to overoxidation. To achieve optimal electrocatalyst performance, a careful balance of adsorption strength and reaction pathway management is required. Proper optimization of these parameters is required to improve efficiency and selectivity in the electrocatalytic process.