Determination of energy band gap of nanocrystalline SbSI using diffuse reflectance spectroscopy

Twelve methods of determining energy band gap $( E g )$ of semiconductors using diffuse reflectance spectroscopy have been applied in investigations of sonochemically produced antimony sulfoiodide (SbSI) consisting of nanowires. It has been proved that the best method of determining $E g$ is based on simultaneous fitting of many mechanisms of absorption to the spectral dependence of Kubelka–Munk function evaluated from the diffuse reflectance data. It allows determining the values of indirect forbidden $E g$⁠, the Urbach energy, and the constant absorption/scattering of the examined semiconductor.