Near-100% spontaneous rolling up of polar van der Waals materials.

Abstract

Rolling two-dimensional materials into one-dimensional nanoscrolls introduces curvature, chirality and symmetry breaking, enabling emergent properties. Conventional methods relying on external driving forces, however, exhibit poor control, low yield and limited reproducibility. Here we report spontaneous scrolling in polar van der Waals materials via an electrochemical intercalation/exfoliation process, enabling scalable nanoscroll production. This self-rolling is driven intrinsically by out-of-plane electric polarization (P⊥), where the magnitude of P⊥ is modulated by the intercalant size. Validated across eight polar materials, this approach achieves virtually 100% yield and reproducibility with defined scrolling direction, surpassing external driving force limitations. The nanoscrolls exhibit layer-independent inversion symmetry breaking and coherently enhanced second-harmonic generation, exceeding two-dimensional flakes by ~100-fold and rivalling leading two-dimensional nonlinear materials. Electrochemical initiation further facilitates metal-ion co-intercalation, yielding ten hybrid nanoscroll architectures. These findings establish a scalable route to create one-dimensional nanostructures and hybrid heterostructures, paving the way for designer quantum solids and van der Waals superlattices in quantum nanodevices.