As people spend around 70–90% of their time indoors, poor indoor air quality represents a major health concern, mainly due to the emission of volatile organic compounds (VOCs) from multiple sources. Conventional air purification technologies primarily remove particulate matter, whereas photocatalysis degrades pollutants into harmless products. Titanium dioxide (TiOâ‚‚) nanoparticles are widely employed as photocatalysts due to their stability, low cost, and non-toxicity. However, their application is limited by UV-light activation and high electron–hole recombination rates. To overcome these limitations, TiOâ‚‚–C₃Nâ‚„ composites were developed to extend light absorption into the visible region and improve charge separation.

TiOâ‚‚–C₃Nâ‚„ composites with different mass ratios were synthesized using a simple ball-milling method. The materials were characterized by Nâ‚‚ physisorption, X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), and scanning electron microscopy (SEM). Photocatalytic activity was first evaluated under visible light in aqueous medium using a standard organic dye. The most efficient composite was subsequently immobilized and tested in a gas-phase photocatalytic system.

The TiOâ‚‚/C₃Nâ‚„ composites exhibited low specific surface area and a higher anatase-to-rutile ratio, thereby enhancing photocatalytic performance. The composite containing 0.9 g TiOâ‚‚ and 0.1 g C₃Nâ‚„ exhibited the highest activity under visible light in liquid medium, achieving 70% degradation. Importantly, this material maintained high photocatalytic efficiency after immobilization and under gaseous conditions, demonstrating its potential for indoor air purification. These results highlight TiOâ‚‚–C₃Nâ‚„ composites as a promising and cost-effective solution for improving indoor air quality under visible light.

Traditional hard metals usually use Co metal as the binder for metal carbides (WC, TiC, VC, etc.), achieving balanced combinations of properties like hardness, toughness, ductility, wear resistance. Co/WC composite has been extensively studied and widely applied in cutting tools, mining and construction, metal forming, wear parts, etc. The primary reasons for choosing Co as the binder material are related to its excellent wetting and sintering properties, a prior combination of toughness, ductility, friction and wear resistance, high thermal stability and so on. However, driven by considerations including health and environmental concerns (e.g., Cobalt is classified as a probable human carcinogen by regulatory agencies such as the International Agency for Research on Cancer (IARC)), cost, supply chain stability, and deficient corrosion resistance in certain environments, academies and industries are exploring various materials as potential alternative binders. High-entropy alloys (HEAs), composed of multi-principal elements, are a promising class of alloy for substituting Co as the binder phase. Designing suitable HEA compositions as the binder phase is however a challenging task. Previous studies are mostly based on the trial-and-error method, and only a small number of HEAs (usually the equiatomic HEAs) have been tested. In the current EU project CoBRAIN, we systematically characterize the key thermodynamic, physical and mechanical properties of HEAs in the large compositional space, and design the binder phase to have the similar properties of Co binder in terms of phase stability, deformation behaviors and magnetic properties, etc. Density functional theory (DFT) calculations have been adopted to study the composition and magnetic dependent phase stability and stacking fault energy, which are critical material properties affecting the transformation-induced plasticity (TRIP) and twinning-induced plasticity (TWIP) effects in the binder phase. Several potential compositions in various HEA systems are identified and further tested as binder in thermal spray coatings to verify the design concept. DFT results, together with experimental and theoretical results from the project, form also as a solid database for developing a fast machine learning method, supporting further optimization and customization of binder phases.

The present study focuses on enhancing ballistic protection, a critical factor in the performance and reliability of modern military equipment. Improving ballistic resistance is essential to ensure the personal safety of military personnel, particularly through optimizing protective vests. In this work, thermal spraying using a plasma jet was performed on Armox ballistic steel substrates, employing both metallic and ceramic powders as feedstock. The coated samples, prepared to predetermined dimensions, were subjected to extensive evaluation of their mechanical and microstructural properties to characterize their behavior in relation to ballistic protection efficiency. Investigations conducted by optical and scanning electron microscopy (SEM) enabled detailed assessments of coating adhesion to the substrate, as well as analyses of the coating morphology, thickness uniformity, and porosity. The interface between the deposited layer and the base material was also examined. To assess the potential of the coatings, tribological tests, including microscratch and microindentation analyses, were performed. The study provides a comparative assessment of the performance of metallic and ceramic coatings, aiming to evaluate the applicability of thermal spray deposits for improving the ballistic resistance of armor plates integrated into individual (body) military protection systems.

Performance of sunscreens is primarily optimized through the development of their organic or mineral filtering systems, i.e. the core of their photoprotective action. However, numerous studies have underscored that the homogeneity of the applied deposit is also key to optimize the effectiveness of a given filtering systems. Quantifying the homogeneity of a coating present a significant challenge, particularly on complex substrates such as skin. Therefore, there is a key challenge in being able to have robust methods to measure deposit homogeneity for both in vitro and in vivo UV tests. This work, focused on developing new quantitative methods for evaluating sunscreen deposit and its homogeneity. Our approach involved adaptation Line-Field Confocal Optical Coherence Tomography (LC-OCT), a technique commonly used in biology, to precisely assess the thickness distribution of sunscreen deposit. For this study, we specifically investigated deposit modifications without changing the filtering system, thereby successfully linking variations in deposit thickness and homogeneity directly to filtration performances. This new method not only can be leveraged to advance the development and improvement of new photoprotective technologies but also paves the way for a more comprehensive understanding and characterization of sunscreen applications, both in vivo and in vitro, leading to improved protection.

Diamond coatings deposited on cemented carbide tools are extensively employed in the machining of non-ferrous materials, including aluminum alloys and composites. A key issue for ensuring a sufficient diamond-coated tool life, especially in milling, is the fatigue strength of diamond coating-substrate interface. Nano-crystalline diamond (NCD) coatings deposited on cemented carbide tools are characterized by high residual stresses. The high level of residual stresses in the diamond film structure are attributed to epitaxial and thermal expansion coefficients mismatch of the diamond coating and its cemented-carbide substrate. Thus, the potential for reducing residual stresses in diamond films deposited on cemented carbide inserts, with the aim of improving their effective interfacial fatigue strength and wear resistance, is of high importance.

NCD coatings were deposited on cemented carbide inserts, and a subset of the coated tools was subsequently annealed under vacuum to decrease residual stresses within the film. Inclined impact tests at ambient temperature were performed on both as-deposited and annealed diamond-coated tools to evaluate their effective interfacial fatigue strength. Depending on the applied impact load, damage initiated at the film–substrate interface after a certain number of impacts, leading to coating detachment and lifting. Residual stresses within the diamond films were quantified through finite element method (FEM) analysis of the impact imprints. In addition, milling experiments were conducted using aluminum foam as the workpiece material to assess the cutting performance of the coated tools. A clear correlation was identified between the interfacial fatigue strength of the diamond coatings and their residual stress state as influenced by annealing. The obtained results show that an impressive enhancement of the effective interfacial fatigue strength and milling performance of diamond-coated tools can be achieved by decreasing the structural residual stresses via appropriate adjustment of the annealing duration and temperature.

MAX phases are a promising material group for high-temperature coating applications. Currently, the search for sustainable MAX phase synthesis and coating techniques suitable for this particular material group is still ongoing. One of the most promising method is cold spray, which prevents the thermally-induced phase changes of the coating material during deposition, while drastically reducing the energy and gas required for the process in comparison to other thermal spraying techniques. In this work, a modified low pressure cold spray (LPCS) system – aerosol cold spray (ACS) has been successfully used to fabricate Ti₂AlC, Cr₂AlC and Ti₃AlC₂ coatings on carbon steel substrate. Structural and microstructural analysis indicated successful deposition of dense and crack-free coating without inducing phase changes during the spraying process using compressed air as process gas. Additionally, post-processing of the coatings by free- and spark plasma sintering methods were tested. The analysis of post-processed coating’s microstructure indicated the increase of interparticle bonding within the coating, however free sintering method resulted in cracking within Ti₃AlC₂ coating, and formation of porosity in Cr₂AlC coating, due to intense diffusion of aluminum towards the carbon steel substrate. This work presents the first successful deposition of MAX phase coatings using a LPCS-based technique, as well as post-processing and characterization of their structural and mechanical properties.

Anodic oxidation of titanium is an electrochemical surface treatment that enables controlled growth of a titanium dioxide (TiOâ‚‚) layer through anodic polarization in an electrolytic environment. The resulting oxide film enhances surface performance by improving corrosion resistance, biocompatibility, and optical response, thereby extending the applicability of titanium across aerospace, biomedical, architectural, and advanced design sectors.

A distinctive feature of anodically oxidized titanium is the formation of interference colors, originating from nanometric variations in oxide thickness and light–matter interaction. These effects allow precise and reproducible tuning of surface appearance without the use of pigments or coatings, offering a robust strategy for functional surface modification.

This work examines the relationship between anodizing parameters, oxide growth behavior, and resulting surface properties, with particular attention to the role of surface condition and processing routes. Experimental investigations were conducted by integrating laboratory-scale anodizing with engineering manufacturing techniques, including additive manufacturing and mechanical surface finishing, in order to evaluate their influence on oxide formation and color uniformity.

The results demonstrate that anodic oxidation can be effectively combined with advanced manufacturing processes to produce titanium surfaces with tailored functional and optical characteristics. This approach highlights the potential of electrochemical surface engineering as a versatile tool for controlling titanium surface properties.

Thin film technologies based on renewable sources, as agri-food residues, are attracting increasing interest as sustainable, high-performance materials for advanced coating applications, such as preservation systems for the postharvest industry. This work explored the ultrasound-assisted functionalization of citrus waste pectin as a bio-based material for coating applications. Pectin extracted from orange peel and pomace residues was modified using pulsed high-power ultrasound (2–5 min), and its performance was compared with untreated and commercial pectin references. Ultrasound treatment induced controlled molecular rearrangements, increasing esterification degree and methoxyl content, so converting citrus pectin into a high-methoxyl form without significant degradation. In addition to a 50~60% increase in its antioxidant performance. Uniform modified pectin-based thin films were fabricated by casting, with thicknesses of 50 - 63 µm. The optimized film formulation (F-HPU-MCP-2) exhibited enhanced properties, including a 70% increase in elongation at break, an improved surface barrier with 60% higher WCA, 45% reduction in water solubility, and a complete ultraviolet light shielding. The coating performance was assessed by applying the optimized film-forming solution as edible coatings on fresh strawberries (cold storage). The coating effectively reduced moisture loss in 15~30%, delayed fungal growth, preserved fruit integrity/firmness and colour, extending strawberries shelf-life for up 10 days. These findings demonstrate high-power ultrasound as an efficient green route for tuning the physicochemical and functional properties of waste-derived biopolymers for development of sustainable thin films/coating systems with enhanced functionality.

Additive manufacturing processes are nowadays widely used for prototyping, as well as for industrial applications, e.g. the production of machine tools. The finished products often suffer from degraded mechanical properties comparatively, as additive manufacturing processes inherently create mechanical property variations among layers. Issues commonly arise due to incomplete fusion, thermal cycling, contamination, anisotropy, porosity and cooling rate variations.

A few different methods have been introduced for both metallic and synthetic materials, which typically include annealing or work hardening. These can be applied to the finished product or during the manufacturing process to improve the interlayer mechanical properties. Regarding work hardening, deep rolling is a common procedure where a spherical indenter is rolled onto the manufactured surface using a controlled force applied perpendicular to the surface. However, this procedure is generally coarse and mostly designated for large surfaces.

We herein introduce micro-forging with the aid of a controlled repetitive impact indenter, to induce precise levels of work hardening onto manufactured surfaces. The force amplitude perpendicular to the treated surface can be adjusted according to the desired level of work hardening. The indenter, made of hard materials like tungsten carbide, hits the processed surface repeatedly at an adjustable rate. The kinematics are completed by either moving the indenter onto the surface or the workpiece underneath the indenter. By adjusting the impact repetition rate and the feed of the surface underneath the indenter, impact overlapping can be achieved and the resulting mechanical properties optimized. The shape of the indenter can also be freely selected for different applications or for creating a texture finish.

Our findings illustrate that interlayer hardness can be drastically increased leading to more robust machine elements. Surface roughness can be adjusted, especially important for further processing like the subsequent application of coatings. Issues arising from increased porosity can be minimized, as the introduced micro-forging process helps to minimize the overall gaps between the material.

The Safe and Sustainable by Design (SSbD) framework offers a solid foundation for comparing the risks and impacts of products and processes. Although it is currently focused on the chemical and material sectors, its principles are highly relevant and could be extended to other industrial fields. In these broader contexts, SSbD can guide the (re)design of products and production systems towards safer and more sustainable outcomes.

The Surfera Plus Network of Excellence is a Spanish project funded by the CDTI (Center for Technological Development and Innovation) through the CERVERA 2023 Program. Its objective is to establish a Network of Excellence to valorize surface functionalization technologies for national, strategic, and socially impactful industrial sectors. The network comprises the national technology centres AIN (Coordinator), TEKNIKER, CIDETEC, IDONEAL, and CTME.

Within this framework, CTME adapted the SSbD methodological guidance originally developed by Abbate et al. for chemicals and materials to the surface treatment sector. This adaptation establishes a design framework that emphasizes sustainability and occupational safety while providing a flexible and adaptive methodology that enables efficient SSbD implementation. The original guidance served as the starting point for developing the adapted methodology. Its capabilities and outcomes were evaluated through two demonstrators developed within the Surfera Plus project, allowing the identification of critical areas requiring intensified efforts or methodological adjustments. In addition, a method to assess socioeconomic impacts was developed, incorporating life cycle cost analysis, critical materials assessment, and social Life Cycle Assessment (social LCA).

The resulting methodology, based on Abbate et al.’s work, includes the identification of critical points, more concise approaches for specific steps, and a social assessment tailored to the surface treatment sector. Except for the LCA step, specific methodologies were developed for all stages, streamlining SSbD application in this field. In line with Abbate et al.’s recommendations, the current approach considers only the intrinsic risks of materials; future developments could incorporate risks associated with individual unit processes.