Adjustable 1D ferroelectricity and ferrielectricity in faceted GeSe nanotubes

Dimensionality reduction of ferroelectric (FE) materials is a pressing task at present due to the increasingly urgent need for miniaturized devices. Here, a set of unprecedented stable one-dimensional (1D) faceted GeSe nanotubes (GNTs) was explored and predicted to be synthesizable within carbon nanotubes. All the GNTs exhibit an axial FE polarization induced by broken inversion symmetry and the polarization intensity can be adjusted by altering their radial dimensions. Both the polarization intensity and Curie temperature can be enhanced by forming double-walled (DW) GNT structures. Different stacking configurations enable DW GNTs to exhibit switchable FE and ferrielectric charge orders. Our results enrich the family of 1D FE systems and provide new insights into the manipulation of 1D FEs. We proposed a set of faceted GeSe nanotubes (GNTs) which can exist in carbon nanotubes. 1D adjustable ferroelectricity and ferrielectricity were found in the single- and double-walled GNTs.