Preparation of controllable-thickness 1T@2H-MoS2 thin films by pulsed laser-induced synthesis and the selective separation of the 1T phase

Abstract

Ultrathin 1T@2H-MoS₂ films have excellent electronic and optical properties, and are potentially applicable in optics, electronics, energy storage, and sensing technology. However, identification of an efficient method to produce 1T@2H-MoS₂ films with controllable thickness is challenging. This study describes the rapid synthesis (5–10 min) of 1T@2H-MoS₂ thin films on Si/SiO₂ substrates by a novel pulsed laser irradiation method. We verify the photodecomposition reaction model by measuring the UV-Vis absorption spectra of the reactants. The thickness of the synthesized MoS₂ film can be controlled by adjusting the concentration of the precursor. Structural characterization confirms that both the 1T and 2H phases exist in the MoS₂ film. The 1T phase enhances the conductive behavior of the MoS₂ film and induces magnetism. Furthermore, pure 1T-MoS₂ can be separated selectively from the MoS₂ film under specific operating conditions using pulsed laser-induced synthesis. This approach is suitable for the synthesis of films of MoS₂ and other 2D materials, including 1T phase-pure films.