Strain-engineered fabrication of high-density aligned graphene-based nanoscrolls via UV-tunable adhesive tapes

Graphene nanoscrolls (GNSs), one-dimensional nanostructures formed by rolling up a single sheet of graphene, exhibit electronic and mechanical properties distinct from the original graphene sheet. Although several methods have been proposed to synthesize GNSs, achieving high-density GNSs with controlled scroll chirality and direction remains challenging. Here, we demonstrate the strain-engineered fabrication of large-scale GNSs using an ultraviolet (UV) light-tunable adhesive tape. The UV tape is stretched to apply tensile strain to graphene stacked on it, and releasing the applied strain by detaching the graphene from the tape results in the formation of GNSs. This strain-assisted method gives isolated GNSs of increased density ( ≈ 380 nanoscrolls per mm) and length (90 μm). This method also allows control of the scroll angle, i.e., chiral angle, by controlling the stretch direction of the tape/graphene stack. The nanoscroll structure allows the intercalation of metal chloride molecules, resulting in an increase of the electrical conductivity. Furthermore, heteronanoscrolls of graphene and MoS₂ are realized by stretching MoS₂/graphene heterostacks, exhibiting clear optical response. Our controlled synthesis of GNSs and heteronanoscrolls provides an opportunity to manipulate nanomaterials through the strain engineering with the functional UV tape.