Scalable synthesis of 2D van der Waals superlattices

TL;DR

This paper introduces a scalable vapor-phase method to synthesize 2D van der Waals heterostructures and superlattices from metal films, enabling improved material properties and potential applications in electronics and catalysis.

Contribution

A novel vapor-phase processing technique for converting metal films into high-quality 2D heterostructures and superlattices with controlled morphology.

Findings

Heterostructures exhibit reduced bandgap and enhanced light-matter interactions.

Superlattices show improved catalytic performance.

Method is scalable and adaptable to various 2D materials.

Abstract

Heterostructure materials form the basis of much of modern electronics, from transistors to lasers and light-emitting diodes. Recent years have seen a renewed focus on creating heterostructures through the vertical integration of two-dimensional materials, including graphene, hexagonal boron nitride, and transition metal dichalcogenides (TMDCs). However, fundamental challenges associated with materials processing have limited material quality and impeded scalability. We demonstrate a method to convert sub-nanometer metal films deposited on silicon and sapphire into TMDC heterostructures through vapor-phase processing. The resulting heterostructures and superlattices exhibit novel properties compared with stand-alone TMDCs, including reduced bandgap, enhanced light-matter coupling, and improved catalytic performance. This robust and scalable synthetic method provides new opportunities to generate a wide range of artificially stacked 2D superlattices with controlled morphology and composition.