Van der Waals heterostructures with one-dimensional atomic crystals

As one of the well-defined classes of low-dimensional materials, one-dimensional (1D) materials and related heterostructures have aroused broad interest due to their unique physical properties and widespread applications over the past decades. The concept of van der Waals (vdW) heterostructure, which has gained great success in superlattice of two-dimensional (2D) layered materials, can be also extended to heterostructures with 1D atomic crystals. Due to the less rigid requirement on lattice matching, versatility of foreign materials with different dimensionalities can be integrated with the 1D templates via non-covalent bonding. Such 1D vdW heterostructures are expected to exhibit intriguing physical properties and functionalities that cannot be realized in single-component 1D material. This review article aims to provide a succinct and critical survey of the emerging 1D vdW heterostructures. We start with an overview of the configuration and summarize the synthetic strategies of 1D vdW heterostructures. Next, we discuss their physical properties with emphasis on those originated from the unique structure–property relationship, including spatial confinement effect and phase transition, band structure and electrical properties, optical properties, thermal properties and environmental stability, and directional mass transport. The emerging applications of 1D vdW heterostructures in electronic, photonic, optoelectronic and energy storage fields are comprehensively overviewed. Last, we conclude with a brief perspective on the opportunities as well as challenges of vdW heterostructures with 1D atomic crystals.