3D printing, or additive manufacturing, is one of the most impactful technologies in recent decades. It relies on the layer-by-layer fabrication of three-dimensional objects from digital models, unlike traditional subtractive techniques that shape parts by material removal. This approach enables high precision, design flexibility, reduced material waste, rapid prototyping, and the realization of complex geometries difficult to obtain with conventional manufacturing.

Despite these advantages, the most widely adopted and cost-effective 3D printing technologies, such as Fused Deposition Modeling (FDM) and Digital Light Projection (DLP), are largely limited to polymeric materials. This aspect drives the development of efficient and cost-effective metallization strategies able to impart metallic properties to 3D printed polymer components. Among available solutions, wet metallization techniques based on liquid electrolytes are particularly attractive in terms of cost and scalability.

A particularly promising way to carry out wet metallization on 3D printed parts is represented by the use of self-activating materials. These materials can be directly 3D printed and incorporate either a catalytic metal or a precursor of a catalytic species, such as a metal salt. When a precursor is used, it can be converted into the active catalyst through chemical reduction. Embedding the catalytic species within the printed part removes the need for the etching and surface activation steps typical of standard electroless plating, providing improved adhesion, coating uniformity and the possibility of selective metallization.

In the present work, self-activating composites containing non-precious transition metal salts are developed, 3D printed, and metallized. Nickel and copper salt microparticles are dispersed in a DLP resin to obtain printable composites. After printing, surface-exposed precursors are chemically reduced to form metallic nuclei, which initiate the electroless deposition of NiP and Cu. The resulting coatings are characterized in terms of adhesion, uniformity, and morphology. The possibility of achieving selective metallization is demonstrated as well.

Plating on plastics (PoP) is a crucial process in current industrial practice. Indeed, PoP combines the advantages of polymers (low weight, reduced cost and flexibility) with those typical of metals (aesthetic appearance, wear resistance, high electrical or thermal conductivity and ferromagnetic behavior). For these reasons, PoP finds widespread use across numerous sectors, including the automotive industry, electronics, household goods manufacturing and fashion.

State-of-the-art PoP processes applied to ABS (the most commonly employed polymer), or to other plastic substrates, typically rely on materials that are either hazardous or limited in availability. In particular, the surface etching step necessary to improve metal–polymer adhesion typically involves highly toxic hexavalent chromium compounds. Furthermore, the activation step conventionally requires palladium, a scarce element classified by the European Union as a critical raw material.

Within the framework of the safe-and-sustainable-by-design (SSbD) strategy, the European FreeMe project seeks to remove both Cr(VI) and Pd from the PoP process, ensuring compliance with REACH regulations. In this context, the present study reports on the development of sprayable resin formulations containing appropriate metallic precursors. Owing to the incorporation of these precursors, the materials exhibit self-activating behavior, thereby eliminating the need for conventional etching and activation steps. The embedded precursor is subsequently reduced to its metallic form through immersion in a reducing solution, generating metallic nuclei that initiate the electroless deposition of NiP.

In addition to NiP, copper coatings can also be deposited via electroless plating using a similar approach, as demonstrated by selecting an appropriate metal precursor within the resin and a suitable plating bath. The resulting NiP and Cu layers are thoroughly characterized to assess their uniformity, morphology, phase composition, and adhesion. The resins described in the present study can be directly spray-coated onto ABS substrates, resulting in easy potential industrial implementation.

Wear-resistant coatings and hardfacing technologies are widely applied to soil-engaging agricultural tools to extend service life; however, their influence on wear evolution and contact loading remains insufficiently quantified. This study presents a simulation-based evaluation of hardfacing seam configurations applied to cultivator coulter points, focusing on abrasive wear development and surface loading behaviour. Discrete Element Method (DEM) simulations were performed using ANSYS Rocky to model soil-tool interaction under representative field conditions. Several reinforcement seam arrangements located at the cutting edge were analysed and compared with an unreinforced reference geometry.

To address limitations related to multi-material wear modelling, a dedicated numerical approach was employed, enabling reliable simulation of reinforced geometries during progressive wear. The results indicate that optimized hardfacing seam placement significantly modifies soil flow and contact conditions on the coulter surface. When reinforcement seams were partially worn and actively protecting the cutting edge, volumetric wear of the coulter point was reduced by up to 40% compared to the unreinforced tool. At the end of the simulated wear process, the total wear reduction remained approximately 28%.

Additionally, specific seam configurations generated a soil-lifting effect, reducing the pressure acting on the coulter point working surface by up to 12%, thereby slowing wear progression rather than directly reducing overall draft force. Simulation results showed good qualitative agreement with field measurements, with deviations within approximately 5%, confirming the reliability of the modelling approach. The study demonstrates that DEM-based simulation is an effective tool for optimising hardfacing seam configurations and improving the performance of wear-resistant coatings in agricultural applications.

Surface engineering of biodegradable polymeric nanoparticles offers an effective strategy to regulate interfacial properties, biological interactions, and functional performance in advanced coating systems. In this work, poly(D,L-lactic acid) (PLA)-based nanoparticles were surface-engineered using a folic acid–functionalized chitosan (CS-FA) coating, creating a hybrid organic architecture that integrates biodegradability, biofunctionality, and receptor-specific surface recognition.

The impact of the CS-FA coating on surface and coating performance metrics was systematically investigated. Structural and chemical modification were confirmed by FTIR and NMR spectroscopy, while particle morphology and coating integrity were evaluated by SEM and DLS. Key interfacial properties, including wettability and enzymatic degradation, were assessed under physiological conditions (pH 7.4), demonstrating that FA-functionalized chitosan coatings impart enhanced surface hydrophilicity, a feature that can directly influence diffusion characteristics and stability of the coated nanoparticles. Furthermore, to evaluate biointerface performance, in vitro studies were conducted using immortalized mouse embryonic fibroblasts (iMEFs) and MDA-MB-231 breast cancer cells. Cytocompatibility was confirmed across all formulations, while confocal laser scanning microscopy revealed enhanced cellular association and internalization of CS-FA–coated nanoparticles in MDA-MB-231 cells, attributed to folate receptor–mediated interactions. In contrast, minimal nonspecific uptake was observed in iMEFs, indicating surface-selective behavior.

Overall, the study demonstrated how folic acid–functionalized chitosan coatings can be used to surface-engineer PLA-based nanoparticles with tunable interfacial properties and selective biological interactions. The findings highlight the potential of hybrid organic coatings to simultaneously optimize coating performance and enable targeted drug delivery functionalities within a safe and sustainable materials design framework.

The transition toward Safe and Sustainable by Design (SSbD) coating technologies is accelerating as industry seeks viable, REACH‑compliant alternatives to hard chromium. This work presents an integrated approach combining green electrolyte design, equipment‑level process innovation, and innovation assessment to advance nickel‑based nanocomposite coatings as eco‑conscious replacements for hard chromium. Building on developments from the MOZART project and complementary research at Creative Nano, boric‑acid‑free Ni electrolytes based on organic acids were formulated and reinforced with SiC, graphene, and WS₂ nanoparticles. These systems demonstrated stable dispersion behavior, enhanced nucleation, and significant improvements in mechanical and corrosion‑resistant performance, with microhardness values exceeding 1100 HV and contact angles surpassing 120° under optimized conditions.

Beyond electrolyte chemistry, substantial engineering upgrades were implemented to enable reliable nanocomposite deposition at pilot scale. A 250‑L dual‑tank plating system was modified to incorporate controlled hydrodynamics, continuous electrolyte circulation, and a custom rotating rack for uniform current distribution. A high‑power ultrasonication panel was integrated to promote nanoparticle deagglomeration and enhance mass transport, enabling both pre‑treatment and periodic U/S activation during deposition. These modifications reduced porosity, improved particle incorporation, and strengthened crystallographic texture, particularly along the Ni(111) plane. Pilot‑scale validation on forged steel piston rods confirmed uniform deposition, strong adhesion, and industrial applicability.

In parallel, SSbD principles guided waste minimization strategies, including the elimination of boric acid, reduced sludge formation, improved bath stability, and lower energy consumption through optimized current regimes. Real‑time nanoparticle monitoring technologies further supported predictive bath management and process reproducibility.

Finally, an innovation assessment was conducted through targeted patent landscape analysis to evaluate freedom‑to‑operate, identify emerging trends in Ni‑based nanocomposites, and position the developed technologies within the broader innovation ecosystem.

Overall, the combined advances in chemistry, equipment design, ultrasonication‑assisted processing, and innovation assessment demonstrate a robust pathway toward sustainable, high‑performance Ni‑based nanocomposite coatings capable of replacing hard chromium in demanding engineering applications.

Composite electrochemical coatings (CECs) based on nickel and dispersed functional particles offer an effective route to enhance the mechanical, chemical, and tribological performance of metallic surfaces. In this work, the electrochemical co‑deposition of nickel with Ti₃C₂Tₓ MXene was investigated to develop advanced Ni/MXene nanocomposite coatings with improved functional properties.

The dispersion stability of Ti₃C₂Tₓ MXene was systematically evaluated through the screening of multiple surfactants, first in aqueous media and subsequently in the nickel electrolyte. A sustainable nickel electroplating electrolyte was utilized by substituting boric acid with tartaric acid. Dynamic Light Scattering (DLS) measurements were used to determine hydrodynamic diameter (HDD) and ζ‑potential, enabling identification of the optimal dispersant for stable MXene suspensions.

Using the stable electrolyte, Ni/Ti₃C₂Tₓ composite coatings were produced via direct‑current (DC) electrochemical co‑deposition at current densities of 1, 2, and 5 A·dm⁻². The resulting coatings were comprehensively characterized: surface morphology and MXene distribution were examined by SEM–EDS, while phase composition and elemental content were assessed using PXRD and portable XRF. Mechanical and surface properties were evaluated through Vickers microhardness testing and water contact angle measurements, providing insight into the structure–property relationships governing the performance of the developed nanocomposite coatings.

Plating on plastics (PoP) is widely used in the automotive, electronics, and home appliance industries to enhance mechanical strength, corrosion resistance, and aesthetic quality. Polymer surfaces must be pretreated to enable the electroless deposition of a Ni-P conductive layer, which in turn provides the necessary foundation for the subsequent electroplating steps. Conventional industrial processes typically employ hexavalent chromium (Cr⁶⁺) based etching solutions, which are highly toxic and carcinogenic, along with activators containing palladium (Pd), which is considered as critical raw material and presents significant economic challenges due to its high cost.

This study provides a sustainable and cost-effective alternative to PoP by replacing chromic acid etching with environmentally benign acidic solutions and substituting Pd with Ni for activating ABS, PC-ABS, and Nylon-12 surfaces. Surface chemical modifications, morphology and adhesion were evaluated using FT-IR, water contact angle measurements, SEM-EDX and pull-off adhesion tests. The results demonstrated that uniform, thin and well-adhered Ni-P conductive layers can be deposited on all three polymer substrates. Moreover, the technology was successfully applied to real components with complex geometries that are used in aerospace, home appliances and automotive applications, highlighting its practical viability and reinforcing its contribution to greener surface-coating processes.

Lignin, the second most abundant natural polymer following cellulose, is receiving considerable interest as a renewable resource capable of diminishing dependence on fossil fuels and improving the environmental sustainability of polymer composites [1]. While unmodified lignin offers inherent benefits like thermal stability, flame retardancy and antioxidant properties, its poor compatibility with hydrophobic matrices often limits its incorporation to only a small amount. As a result, a variety of chemical modification strategies are utilized to produce value-added lignin derivatives, hence enhancing its applicability in green polymeric materials [2].

In this work, lignin modified with tyrosine (Lig-Tyr) was incorporated into the HDPE matrix via melt mixing at 190 °C, in five different loadings 1 wt.%, 5 wt.%, 10 wt.%, 20 wt.%, and 30 wt.%. The final composites were characterized in terms of their structure through Fourier-transform infrared spectroscopy (FTIR). Their thermal behavior was evaluated via Differential Scanning Calorimetry and revealed no significant alteration of the HDPE properties after lignin incorporation, while mechanical behavior was deteriorated especially in filler loadings higher than 10 wt.%. Finally, the investigation of antioxidant properties through the DPPH method suggested enhanced antioxidant capacity compared to the neat polymer.

Acknowledgements

This project has received funding from the European Union's Horizon Europe Framework Programme under Grant Agreement No 101058449. Views and opinions expressed are however those of the author(s) only and do not necessarily reflect those of the European Union or HADEA. Neither the European Union nor the granting authority can be held responsible for them.

The increasing demand for sustainable, multifunctional coatings has driven research toward bio-based additives capable of enhancing thermal stability, durability, and long-term performance while reducing environmental impact. In this work, Kraft lignin was chemically modified with phosphorus (P), nitrogen (N), and combined phosphorus-nitrogen (P-N) elements and evaluated as a multifunctional bio-based additive in high-density polyethylene (HDPE) matrices. The modified lignins were incorporated into HDPE at loadings ranging from 1 to 30 wt% via melt processing, and the resulting materials were systematically characterized with respect to thermal behavior, oxidative stability, flame retardancy, mechanical performance, and surface properties. P- and N-functionalized lignin significantly enhanced char formation and increased the temperature of maximum thermal degradation, indicating improved thermal protection mechanisms. UL-94 vertical burning tests revealed reduced melt dripping and prolonged burning times compared to neat HDPE, confirming the effectiveness of lignin-based additives in mitigating flammability. At low additive loadings (≤5 wt%), the composites maintained or slightly improved mechanical properties, while higher loadings led to a gradual reduction of properties, associated with filler aggregation. Furthermore, the composites exhibited markedly improved antioxidant performance, as evidenced by extended oxidation induction times and enhanced DPPH radical scavenging activity, highlighting their potential for improved aging resistance in protective coatings. Contact angle measurements demonstrated that the incorporation of modified lignin maintained or improved surface hydrophobicity, a key surface property for polymer-based coating applications.

Layer-by-layer (LbL) deposition is a versatile method to prepare thin film coatings with alternating layers of oppositely charged materials. The layers may be installed using different processes such as drop casting, dip coating, spin coating, spray coating, the choice of which have a significant impact in accurate reproducibility and the electrochemical properties of the resulting hybrid electrode.

The last few years a great intertest has being taken in the development and functionalization of 2D materials in electronic applications mainly due to their high conductivity. MXenes possess a unique combination of physicochemical characteristics that render them particularly attractive for sensing applications. Their electrical conductivity facilitates rapid electron transfer, which is essential for effective signal generation in electrochemical sensors. At the same time, their large surface area coupled with the presence of diverse surface terminations such as -OH, -O, -F, and -Cl provides abundant active sites and allows their functionalization with other materials such as Graphene Oxide (GO), leading to the formation of hybrids with improved and synergistic functional properties.

In this study, LbL deposition of Ti₃C₂Tₓ MXenes and GO was employed for the modification of GCEs using two different assembly approaches, namely dip coating and drop casting. The influence of the deposition method on film formation, structure and interfacial properties of the MXene-GO hybrid electrodes were assessed using a combination of structural, surface, and electrochemical techniques, including Scanning Electron Microscopy (SEM), X-ray Diffraction (XRD), Water Contact Angle measurements (WCA), Cyclic Voltammetry (CV), Electrochemical Impedance Spectroscopy (EIS) and cycling stability tests. Results showed that the LbL-assembled hybrid coatings significantly enhanced the electrochemical performance of the modified electrodes compared to bare GCEs, while clear differences between dip-coated and drop-cast electrodes were observed in terms of charge transfer resistance, surface wettability, and electrochemical stability. Based on the above results, the developed hybrid electrodes could be used as electrochemical sensing platforms for glucose and lactate detection, exploiting the synergistic properties of MXenes and GO.