Sustainable printing of 2D/MXene inks for smart surfaces

Abstract Printable inks based on two-dimensional (2D) materials, in particular MXenes and graphene, are increasingly used to create smart surfaces. At sub-micron thickness, these flakes offer an outstanding electrical conductivity. Moreover, they are capable of bending without cracking and can be printed at low temperatures on plastics, papers, and fabrics. A particular emphasis in this issue relates to sustainability-aspects in related studies. Therefore, this special issue considered (i) low-hazard, water-based inks, (ii) MXene formulations stabilized using antioxidants, surface treatments, or improved storage, and (iii) clear correlations between ink recipe, printing modality (inkjet, screen, gravure, aerosol-jet), and performance. Device-level examples have been asssessed including transparent EMI shields, gentle-voltage heaters and defoggers, conformal antennas, sensing skins, and co-printed micro-supercapacitors. Life-cycle and techno-economic analyses that tie footprint and cost to delivered function were also other subjects of interest.