Synthesis of Atomically Thin Transition-Metal Dichalcogenide Alloys

Ming-Deng Siao^1*, Yung-Chang Lin², Kuei-Yi Lee³, Yu-Ting Hsiao⁴, Shou-Yi Chang⁴, Po-Wen Chiu¹

¹Institute of Electronic Engineering, National Tsing Hua University, Hsinchu, Taiwan
²National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba, Japan
³Department of Electronic Engineering, National Taiwan University of Science and Technology, Taipei, Taiwan
⁴Department of Materials Science and Engineering, National Tsing Hua University, Hsinchu, Taiwan

* Presenter:Ming-Deng Siao, email:tzcoba01@gmail.com

Transition-metal dichalcogenides belong to the big family of 2D layered materials and have recently drawn great attention in the research community due to their fascinating physical properties in a reduced dimension. Here, we show the incorporation of a substantial among of foreign atoms into the lattice of WS₂ host layers by means of solid-state reaction, forming a novel alloyed 2D layered materials. Scanning transmission electron microscopy is used to identify the substitution of various transition-metal atoms to the W sites. The resultant structure appears to be either 2H or 1T phase, depending on the concentration of the foreign atoms in the lattice. Raman spectra show that new Raman active modes appear in the low frequency in additional to those of pristine WS₂. Photoluminescence is also used to characterize the excitonic emission induced by the new structure of the alloyed WS₂ layers.

Keywords: 2D layered materials, Transition-metal dichalcogenide alloys