Tuning MoS2 reactivity toward halogenation†
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.