Effect of plasma voltage on sulfurization of α-MoO3 nanostructured thin films

Abstract

In this report, the effect of plasma voltage on plasma assisted sulfurization (PAS) of vertically aligned molybdenum trioxide (α- MoO3) nanoflakes (NFs) on glass substrates has been studied systematically. MoO3 NFs were deposited using plasma assisted sublimation process. These nanoflakes were subjected to H2S/Ar plasma at two different plasma voltages 600 and 1000 volts; to study the effect of plasma ionization on degree of sulfurization of MoO3 into MoS2. XRD and Raman analysis show that film sulfurized at 1000 volts have relatively higher degree of conversion into MoS2, as more intense peaks of MoS2 and MoO2 are obtained than that sulfurized at 600 volts. HRTEM of sulfurized film shows that outer surface of nanoflake has been converted into MoS2 (4-5 monolayers). Meanwhile, MoO3 was reduced into MoO2 as confirmed by XRD and Raman results. All the observed results are well in consonance with each other.