ConspectusThe development of two-dimensional (2D) materials and their van der Waals (vdW) heterostructures has substantially advanced research in low-dimensional physics and stimulated the exploration of related devices. Further reducing the dimensionality to the one-dimensional (1D) limit often gives rise to more pronounced confinement effects, thereby creating new opportunities for electronic, optoelectronic, and energy-related applications. In this context, 1D vdW heterostructures are typically constructed by assembling 2D counterparts into heteronanotube architectures with coaxial core-shell geometries, while the concept has also been extended to nanotubes encapsulating nanochains, nanowires, or nanoribbons. Compared with their 2D counterparts, 1D systems exhibit strong radial confinement and curvature-induced effects, which together endow them with unique optical, electrical, and thermal properties. The 1D geometry enhances the anisotropy of light-matter interactions and facilitates the efficient axial transport of charge carriers and energy. Meanwhile, the fully encapsulated core-shell configuration effectively suppresses environmental perturbations, providing an ideal platform for probing intrinsic material properties and improving device stability. Accordingly, this Account summarizes recent progress in the field of 1D vdW heterostructures, highlighting representative contributions from our group together with those from many research teams worldwide with the aim of systematically reviewing the current research landscape and outlining future directions. First, the Account presents designed synthesis strategies for 1D vdW heterostructures from the perspectives of component regulation, structure modulation, and orientation control, emphasizing that rational construction of heterostructure composition and architecture can be achieved through designed synthesis. To facilitate a better understanding of the formation process, the Account then discusses the growth mechanism of 1D vdW heterostructures, pointing out that the growth of the outer shells generally follows an open-end growth mode, while no pronounced chiral correlation was observed between different shells. By coaxially integrating distinct 1D building blocks, 1D vdW heterostructures preserve the intrinsic properties of individual components, while their optical, electrical, and thermal behaviors are synergistically influenced by component selection, radial confinement, and interfacial interactions. These emergent physical properties, which distinguish 1D vdW heterostructures from single-component systems or 2D heterostructures, have been preliminarily investigated in several model systems and provide an important physical foundation for subsequent studies. Based on these property advantages, this Account further discusses the application potential of 1D vdW heterostructures in electronic devices and optoelectronic devices as well as catalytic and energy-storage systems. Given that only about five years have passed since the breakthrough realization of 1D vdW heterostructures, research on their synthesis, mechanisms, properties, and practical applications remains at an early stage, and significant challenges still hinder their engineering and commercialization. Future efforts focusing on expanding material libraries and achieving scalable fabrication are expected to advance the development and application of 1D vdW heterostructures.
Lu et al. (Mon,) studied this question.