Interface structure and strain controlled Pt nanocrystals grown at side facet of MoS₂ with critical size

The heterostructure of transition metal nanocrystal on two-dimensional (2D) materials exhibits unique physical and chemical properties through various interfacial interactions. It has been established that the atomic structure and strain in the vicinity of the interface determine the band structure and phonon modes of the nanocrystal, regulating the optical and electrical properties of such heterostructures. Hence, metal–support interfacial engineering is a demonstrated approach to acquiring desired properties of the nanocrystals. However, a fundamental understanding of the interfacial structures remains elusive and precise control of the interactions has yet achieved. Herein, we explore the regulation of interface on MoS₂ supported Pt nanocrystals which were prepared by reducing ultrasonic dispersed potassium chloroplatinate. The Pt-MoS₂ heterostructure interface was systematically studied by aberration corrected transmission electron microscopy. Three types of Pt-MoS₂ interfaces with distinct atomic configurations were identified. The strain within the Pt nanocrystals is sensitive to the atomic configuration of the supporting MoS₂, which regulates the size of the Pt nanocrystals. These results provide insights on tuning of nanocrystal strain, paving the way for precise control of 2D semiconductor heterostructures.