## 6 Conclusions and Outlook  
Graphene is foreseen as the breakthrough material of the 21 st century. Nevertheless, since there is not a convenient mass-production method so far, other graphene-family products already industrially available are expanding in the market. In particular GnPs are receiving increased interest considering their nano-powder form and appealing chemo-physical properties, which make them a material of choice for advanced nanocomposites. In this review, we mostly concentrated on GnP-based emerging fields, such as flexible and wearable electronics, smart sensing, and reinforced biocomposites. GnPs-based flexible electronics was thoroughly investigated and appears to have made a significant impact already. Many different approaches were proposed; freestanding GnP films and GnP inclusion in polymers are two examples. However, the most promising results were obtained so far by functionalizing flexible plastic substrates with pure nanoflakes or with polymer-GnPs conductive inks. With such approaches, researchers obtained durable and high-performance devices such as antennas, compliant electrodes for energy applications, and lightweight electromagnetic interference shielding films. Furthermore, extensive use of cellulose substrates, sometimes coupled with biopolymers, has been shown to be promising for the construction of sustainable flexible GnP-based technologies, and for an eco-friendly electronic waste management [192]. Wearable electronics require flexibility, foldability, stretchability, and washability, and at the same time, the ability to maintain a satisfactory electrical conductivity [48]. Nanocomposites, in general, are suitable for conductive wearable technologies [80] due to their intrinsic plastic mechanical properties and ease of manufacturing, and to the large spectra of properties accessible with different nanoparticles. Nonetheless, there is still the need for significant efforts to bring about the commercialization of reliable and washable GnP-based materials for innovative wearable and electrical conductive technologies. New and innovative approaches which bind conductive nanoflakes to textiles, even under severe mechanical stresses and laundry cycles, still need to be implemented. In contrast, GnP-based smart sensing has already made promising progress. Ad-hoc material combinations that ensure stretchability and tunable electrical features appear to have made a significant impact as new generation wearable sensor technologies. In particular, since graphene-based material has exhibited one of the highest gauge factors ever reported, strain sensing mechanisms have somewhat matured for many uses, ranging from structural and human health monitoring to automotive and sports applications. So far, the combination of PDMS and GnPs were mainly explored, but there are further possibilities considering other elastomeric materials like thermoplastic polyurethanes, rubbers (e.g., nitrile and natural types), and gel-like constructs such as silly putty. Applications such as tactile devices and electronic robotic skins will benefit from the spread-out of GnPs-based smart sensors. Last but not least, we reviewed the recent advances in GnP-reinforced biopolymer composites. There are already commercial products like skis or tires which benefits from GnP inclusion in oil-derived polymers. Lately, however, the need to reinforce biopolymers also emerged as a strategy to fill the performance gap between traditional long-lasting polymers and bioplastics. Through these strategies, wider use and larger scale use of biopolymers are targeted also for structural applications. PLA is the most investigated bioplastic coupled with GnPs. It has already shown satisfactory results. Indeed, there are already companies marketing GnPs-reinforced PLA 3D printing filaments. In contrast, additional efforts are required for effective GnP inclusion inside other bio-polyesters (likepolycaprolactone), starches, and cellulose-based materials.