Tuning MoS2 reactivity toward halogenation

Abstract

MoS₂ is a material with great potentialities in electronic applications. Tuning its properties by halogenation is a possible route to expand its applicability. Herein, we propose XeF₂ exposure and photochemical chlorination as halogenation techniques of MoS₂ monolayers. The XeF₂ reaction with MoS₂ causes S removal and F incorporation in a single processing step, with the degree of fluorination being controlled by the exposure time. Cl insertion into MoS₂ was achieved by sputtering MoS₂ with Ar and subsequent photochemical chlorination. Sputtering creates S vacancies which act as incorporation sites for Cl. The concentration of these vacancies determines a balance between etching and Cl incorporation. These results provide a new perspective in the use of halogenation as a tool for modification of MoS₂.