Effect of sulfur deficiency on the structural, optical and electronic properties of MnS nanostructures

Abstract

In the current work, the effect of sulfur deficiency on the structural, optical and electronic properties of MnS nanostructures has been investigated. Non-stoichiometric MnS nanostructures (MnS1−x, x = 0, 0.03 and 0.05) samples were synthesized via thermolysis procedure. X-ray diffraction technique using Rietveld refinement procedure was used to identify the different phases percentages, average crystallite size and lattice parameters in different samples. The effect of sulfur deficiency on the different vibrational bands of MnS1−x was explored using Fourier transform infrared (FTIR) technique. UV–visible diffused absorption technique was applied to investigate the absorption, refractive index and optical conductivity of the samples. The energy gap of the system reveals a nonlinear optical bowing effect. Nano MnS1−x semiconductor shows a UV–visible spectra emission depending on Mn to S ratio in the prepared sample. Different electronic parameters (extinction coefficient, dielectric constants, absorption coefficient, refractive index and energy loss function) for (α, β and γ) stoichiometric and non-stoichiometric MnS phases are also explored using the density functional calculation (DFT) and correlated with the obtained experimental results.