Van der Waals Heterostructures by Design: From 1D and 2D to 3D

Heterostructures with designable electronic interfaces represent the material foundation for modern electronic and optoelectronic devices. The conventional heterostructures rely on covalent bonds to integrate the constituent materials with strict lattice-matching requirements. The use of van der Waals (VDW) force allows a bond-free strategy to integrate a wide range of materials, including zero-dimensional (0D) nanoparticles, one-dimensional (1D) nanowires, two-dimensional (2D) nanosheets, and three-dimensional (3D) bulk materials, beyond the reach of conventional heterostructures, creating versatile artificial VDW heterostructures with nearly arbitrary modulation of chemical compositions and electronic structures by design. In this review, we start with a brief review of the unique attributes and merits of VDW heterostructures and then highlight a series of example heterostructures assembled from various low-dimensional materials, including 1D/1D, 0D/2D, 1D/2D, 2D/2D, 2D/3D, and 3D-3D heterojunctions and devices. We will conclude with a prospect on the new opportunities and emerging challenges arising in these unconventional heterostructures.