Thickness-dependent bandgap tunable molybdenum disulfide films for optoelectronics

Abstract

Thickness-dependent bandgap tunable MoS₂ has significant potential applications in electronic and optoelectronic devices. Here, we report an aqueous solution approach to grow thickness-controlled MoS₂ films. The thicknesses of the MoS₂ films can be readily changed from 50 nm to 2.5 nm, corresponding to bandgaps modulated from 1.50 eV to 1.64 eV. Remarkably, MoS₂ films with various thicknesses are expediently realized by simple adjustment of the precursor concentration. Microscopic and spectroscopic analyses illustrate that the as-grown MoS₂ films are uniform and high quality. Photoresponse tests demonstrate that the as-grown MoS₂ films have fast responses to light and good stability.