Semiconducting colloidal quantum dots and their assemblies exhibit superior optical properties owing to the quantum confinement effect. Thus, they are attracting tremendous interest from fundamental research to commercial applications. However, the electrical conducting properties remain detrimental predominantly due to the orientational disorder of quantum dots in the assembly. Here we report high conductivity and the consequent metallic behaviour of semiconducting colloidal quantum dots of lead sulphide. Precise facet orientation control to forming highly-ordered quasi-2-dimensional epitaxially-connected quantum dot superlattices is vital for high conductivity. The intrinsically high mobility over 10 cm² V⁻¹ s⁻¹ and temperature-independent behaviour proved the high potential of semiconductor quantum dots for electrical conducting properties. Furthermore, the continuously tunable subband filling will enable quantum dot superlattices to be a future platform for emerging physical properties investigations, such as strongly correlated and topological states, as demonstrated in the moiré superlattices of twisted bilayer graphene.

由于量子限制效应，半导体胶体量子点及其组件表现出优异的光学特性。因此，它们吸引了从基础研究到商业应用的巨大兴趣。然而，主要由于组件中量子点的定向无序，导电特性仍然是有害的。在这里，我们报告了硫化铅的半导体胶体量子点的高导电性和随之而来的金属行为。精确的面取向控制以形成高度有序的准二维外延连接的量子点超晶格对于高导电性至关重要。^{超过 10 cm 2}  V ⁻¹  s ⁻¹的本征高迁移率和温度无关的行为证明了半导体量子点在导电性能方面的巨大潜力。此外，连续可调的子带填充将使量子点超晶格成为新兴物理特性研究的未来平台，例如强相关和拓扑状态，如扭曲双层石墨烯的莫尔超晶格所示。