Optical and photoluminescence modulation in monolayer molybdenum sulfide thin films via electrochemical deposition: Exploring the influence of deposition voltage and time

Abstract

Monolayer Molybdenum Disulfide (MoS2) exhibits a direct bandgap characterized by strong visible photoluminescence, high on/off ratio, high optical transparency, low dissipation rate, and light absorption in a wide energy spectrum. The influence of different deposition voltages and durations on the optical and photoluminescent characteristics was investigated using Raman spectroscopy, UV–visible spectrophotometry, and photoluminescence spectroscopy. All samples were analyzed for optical properties to confirm their suitability for optoelectronics. The energy band gap and Urbach energy (band tail width) of all films were 1.87 to 2.52 eV and 0.31 to 0.49 eV, respectively. The findings reveal a correlation between enhanced absorption properties and a decrease in the bandgap of the semiconducting film layers, implying the potential utility of the deposited films as efficient solar absorbers. Furthermore, the improved transmittance observed within the visible wavelength range suggests their applicability as effective window layers in thin-film photodiodes. It was established that varying the voltage and time of deposition alone can enhance the optoelectronic performance of the material in any device.