Bio-based resources are proposed as next-generation materials for advanced application. Among them, silk fibroin, a protein-based material generally obtained from Bombyx mori cocoons, is considered to play an increasing role in the development of a more sustainable generation of devices. In this review, the silk fibroin molecular structure and its original properties are presented, together with a wide overview of the available modifications and processing methods to reach custom structural and functional variations.

Lanthanoid organic frameworks (LOFs) stand out as an important class of functional materials. The possibility to employ a great range of metals and ligands lead to the formation of varied and highly porous structures, with diverse applications. The presence of lanthanoid ions favours the improvement of the optical, magnetic and redox properties of MOFs. This review aims to demonstrate the state of the art of LOFs, emphasizing the chemical properties of trivalent lanthanoid ions and the carboxylic based-ligands used in their construction, as well as the main characterization methods and outstanding applications as gas storage, permanent magnets, catalysis, luminescence, drug delivery and so on.

Nowadays, there is increasing concern in transportation engineering about the use of techniques less harmful to the environment and also about road safety. Heterogeneous photocatalysis based on the application of semiconductor materials onto asphalt mixtures is a promising technology because it can mitigate air pollution and road accidents. The functionalized asphalt mixtures with photocatalytic capability can degrade pollutants, such as damaging gases and oil/grease adsorbed on their surface, from specific reactions triggered by sunlight photons, providing significant environmental and social benefits. In this article, a review of photocatalysis applied in asphalt mixtures is presented. The most important characteristics related to the functionalization of asphalt mixtures for photocatalytic applications and their corresponding characterization are presented, and the achieved main results are also discussed.

Nanocarbonaceous materials with specific geometries and physicochemical properties allow the development of high-performance polymer-based smart composite materials. Among them, chemical treatments of graphene allow tailoring its electrical conductivity and, therefore, tuning functional response of materials for sensing applications. Polymer-based nanocomposites have been developed from styrene–ethylene–butylene–styrene (SEBS), a high deformation thermoplastic elastomer, and different graphene-based fillers, including graphene oxide (GO), reduced graphene oxide (rGO), and graphene nanoplatelets (G-NPLs). It is shown that the electrical conductivity shows a percolation threshold around 2 wt % for GO and rGO, remaining nearly independent of the filler content for G-NPL filler contents up to 6 wt %. Furthermore, GO/SEBS and rGO/SEBS composites show high piezoresistive sensibility with gauge factors ranging from 15 up to 120 for strains up to 10%. Thus, GO/SEBS and rGO/SEBS composites can represent a new generation of materials for strain sensor applications, as demonstrated in their implementation in a hand glove prototype with finger movement monitoring.

Polymer composites comprising the ionic liquid (IL) [Bmim][FeCl4] and poly(vinylidene fluoride) (PVDF) have been developed for humidity sensing applications. Different IL contents (5, 10, and 20 wt %) were incorporated into the PVDF matrix and the morphological, physical–chemical and electrical properties of the composites evaluated, together with their humidity sensitivity response. Higher IL contents (20 wt %) induce a porous morphology in the composites. Further, IL incorporation leads to the crystallization of PVDF in the electroactive β phase, which content increases with the incorporation of IL into the polymer. The thermal stability of the composites decreases with increasing IL content. The humidity sensing response of the composites was evaluated with relative humidity variations from 35 to 90%. It is shown that all composites exhibit a linear resistance variation with the relative humidity, the sensitivity to humidity variations increasing linearly with the IL content. The developed materials show a strong potentiality for printable humidity sensors.