Enhancement in field emission of MoS2 nanosheets prepared in water using laser ablation method

Abstract

The laser ablation of a noble target material in a liquid is known as an alternative physical method for nanostructure fabrication. In the present study, the nanosecond laser ablation is used to irradiate MoS2 in water to produce MoS2 nanosheets. The experiments of laser ablation time of 20 minutes and 120 minutes have been carried out to study their field emission properties. Transmission electron microscopy (TEM) and Raman spectroscopy have been used to reveal surface and structural morphology. It is observed that the laser ablation time is an important factor in determining the size of MoS2 nanostructure. The Raman spectra of laser ablation confirm the formation of MoS2 nanosheets and removal of molybdenum oxide species. The TEM shows the size of MoS2 microsheet has been reduced from 2 [Formula: see text]m to 400 nm after the laser ablation treatment. It is found that the turn-on fields are reduced and current densities of MoS2 are increased after the laser ablation. The enhancement in the field emission characteristics of MoS2 is due to the reduction in the size of MoS2 and removal of molybdenum oxide species. The nanostructures produced by laser ablation may be used for optoelectronic application.