Pulsed Laser Deposited Zeolite Coatings on Femtosecond Laser-Nanostructured Steel Meshes for Durable Superhydrophilic/Oleophobic Functionalities

Ultrafast laser structuring has proven to alter the wettability performance of surfaces drastically due to controlled modification of the surface roughness and energy. Surface alteration can be achieved also by coating the surfaces with functional materials with enhanced durability. On this line, robust and tunable surface wettability performance can be achieved by the synergic effects of ultrafast laser structuring and coating. In this work, femtosecond laser-structured stainless steel (SS-100) meshes were used to host the growth of NaAlSi2O6–H2O zeolite films. Contact angle measurements were carried on pristine SS-100 meshes, zeolite-coated SS-100 meshes, laser-structured SS-100 meshes, and zeolite-coated laser-structured SS-100 meshes. Enhanced hydrophilic behavior was observed in the zeolite-coated SS-100 meshes (contact angle 72°) and in laser-structured SS-100 meshes (contact angle 41°). On the other hand, superior durable hydrophilic behavior was observed for the zeolite-coated laser-structured SS-100 meshes (contact angle 14°) over an extended period and reusability. In addition, the zeolite-coated laser-structured SS-100 meshes were subjected to oil–water separation tests and revealed augmented effectuation for oil–water separation.

Fluidized Bed Combustion and Gasification of Fossil and Renewable Slurry Fuels

This article provides a comprehensive review of the state of the art and more recent developments of the thermochemical treatments of slurry fuels in fluidized beds (FB). The review focuses on FB combustion and gasification of slurry fuels based on coal, biomass, sludge, and wastes from industry, agriculture, and the civil sector. The investigations at research and industrial levels over the last decades are presented and discussed, highlighting the adopted technological solutions, the results in terms of feasibility and efficiency, and the perspectives of future development. The different behavior between bubbling and circulating beds was addressed, in particular the optimal choice depending on the process (combustion/gasification/pyrolysis) and fuel properties (e.g., water content). Fundamental studies on interactions between the slurry fuels and the hot bed materials are also reviewed. The cumulative trend of reviewed investigations over the last decades depicts the abandonment of coal-based mixtures used in large plants, and the growing interest in the use of biomass-based slurries for small size application. In this respect, the shift from coal to biomass opens new challenges because of the different properties of biomass (density, fibrous structure, spontaneous degradation, hydrophilic behavior, etc.). Biomass-based slurries circumvent problems posed by using solid dry biomass, particularly in handling, storing, and feeding. Although slurry fuels represent a narrow sector, the results of the research investigations and the experience gained with coal can be exploited to contribute to the achievement of a circular approach based on renewable resources in the near future.

Functional 2D MXene Inks for Wearable Electronics

Inks printing is an innovative and practicable technology capable of fabricating the next generation of flexible functional systems with various designs and desired architectures. As a result, inks printing is extremely attractive in the development of printed wearables, including wearable sensors, micro supercapacitor (MSC) electrodes, electromagnetic shielding, and thin-film batteries. The discovery of Ti3C2Tx in 2011, a 2D material known as a MXene, which is a compound composed of layered nitrides, carbides, or carbonitrides of transition metals, has attracted significant interest within the research community because of its exceptional physical and chemical properties. MXene has high metallic conductivity of transition metal carbides combined with hydrophilic behavior due to its surface terminated functional groups, all of which make it an excellent candidate for promising inks printing applications. This paper reviews recent progress in the development of 2D MXene inks, including synthesis procedures, inks formulation and performance, and printing methods. Further, the review briefly provides an overview of future guidelines for the study of this new generation of 2D materials.

Analysis of the behavior of a biomaterial based on wollastonite/TCP in the implant process of an experimental model of critical bone defects

This study analyzes the clinical, macroscopic and radiographic characteristics of a biomaterial with different proportions of wolastonite (W) and tricalcium phosphate (TCP) on bone tissue regeneration during the implantation process of an experimental model of critical bone defects. Fifteen Wistar rats were used, randomly distributed in 5 groups (n = 3), with a bone defect created on an 8.0 mm diameter calvaria. 4 groups received implants with different proportions of W%/TCP%, referred to as W20/TCP80, W40/TCP60, W60/TCP40 and W80/TCP20. The fifth control group (GC) was filled with blood clot only. Clinical evaluation was performed every 24 hours, and after 7 days, the animals were euthanized. The calvaria were dissected and analyzed macroscopically and by radiography. All study groups showed a satisfactory clinical evolution. The macroscopic analysis showed filling of the bone defect with granules surrounded by newly formed tissue, and the radiographic analysis showed different patterns of displacement of the biomaterial. The study concluded that the different proportions of W%/TCP% were well tolerated by the study groups and demonstrated biocompatibility. The enhanced hydrophilic behavior of the W40/TCP60, W60/TCP40 and W80/TCP20 groups favored the application in the experimental model in vivo.

Effect of Cu2O Substrate on Photoinduced Hydrophilicity of TiO2 and ZnO Nanocoatings

The effect of a Cu2O substrate on the photoinduced alteration of the hydrophilicity of TiO2 and ZnO surfaces was studied. It was demonstrated that the formation of heterostructures Cu2O/TiO2 and Cu2O/ZnO strongly changed the direction of the photoinduced alteration of surface hydrophilicity: while both TiO2 and ZnO demonstrate surface transition to superhydrophilic state under UV irradiation and no significant alteration of the surface hydrophilicity under visible light irradiation, the formation of Cu2O/TiO2 and Cu2O/ZnO heterostructures resulted in photoinduced decay of the surface hydrophilicity caused by both UV and visible light irradiation. All observed photoinduced changes of the surface hydrophilicity were compared and analyzed in terms of photoinduced alteration of the surface free energy and its polar and dispersive components. Alteration of the photoinduced hydrophilic behavior of TiO2 and ZnO surfaces caused by formation of the corresponding heterostructures with Cu2O are explained within the mechanism of electron transfer and increasing of the electron concentration on the TiO2 and ZnO surfaces.

Color Fixation Strategies on Sustainable Poly-Butylene Succinate Using Biobased Itaconic Acid

Biopo-lybutylene succinate (bioPBS) is gaining attention in the biodegradable polymer market due to its promising properties, such as high biodegradability and processing versatility, representing a potential sustainable replacement for fossil-based commodities. However, there is still a need to enhance its properties for certain applications, with aesthetical and mechanical properties being a challenge. The aim of the present work is to improve these properties by adding selected additives that will confer bioPBS with comparable properties to that of current counterparts such as polypropylene (PP) for specific applications in the automotive and household appliances sectors. A total of thirteen materials have been studied and compared, being twelve biocomposites containing combinations of three different additives: a commercial red colorant, itaconic acid (IA) to enhance color fixation and zirconia (ZrO2) nanoparticles to maintain at least native PBS mechanical properties. The results show that the combination of IA and the coloring agent tends to slightly yellowish the blend due to the absorbance spectra of IA and also to modify the gloss due to the formation of IA nanocrystals that affects light scattering. In addition, for low amounts of IA (4 wt %), Young’s Modulus seems to be kept while elongation at break is even raised. Unexpectedly, a strong aging affect was found after four weeks. IA increases the hydrophilic behavior of the samples and thus seems to accelerate the hydrolization of the matrix, which is accompanied by an accused disaggregation of phases and an overall softening and rigidization effect. The addition of low amounts of ZrO2 (2 wt %) seems to provide the desired effect for hardening the surface while almost not affecting the other properties; however, higher amounts tends to form aggregates saturating the compounds. As a conclusion, IA might be a good candidate for color fixing in biobased polymers.

In-vitro assessment of appropriate hydrophilic scaffolds by co-electrospinning of poly(1,4 cyclohexane isosorbide terephthalate)/polyvinyl alcohol

Textile-based Scaffolds preparation has the attractive features to fulfill the stated and implied needs of the consumer but there are still challenges of stability, elongation, appreciable bio-compatibility, and stated hydrophilic behavior. To overcome these challenges, the authors tried to fabricate a scaffold by blending of two highly biocompatible polymers; polyvinyl alcohol and poly(1,4 cyclohexane isosorbide terephthalate) through co-electrospinning. The resultant scaffold by the stated innovative approach evaluated from different characterizations such as dimensional stability/morphology was evaluated by scanning electron microscopy, chemical interactions by that Fourier transmission infrared spectra, wetting behavior was analyzed by a static angle with a contact angle meter from drop method, elongation was examined by tensile strength tester and in-vitro assessment was done by MTT analysis. Based on verified results, it was concluded that PVA/PICT scaffold has a potential for dual nature of hydrophilicity & hydrophobicity and appreciable cell culture growth, stated dimensional stability and suitable elongation as per requirements of the nature of scaffold.