Use and misuse of the Kubelka-Munk function to obtain the band gap energy from diffuse reflectance measurements

The determination of the optical band gap energy (Eg) is important for optimization generation electron/hole pairs in semiconductor materials under illumination. For this purpose, classical theory proposed by Kubelka and Munk (K-M) has been largely employed study amorphous polycrystalline materials. In paper, authors demonstrate, step step, how to use K-M function apply it thoroughly Eg TiO2 powder (pressed at different thicknesses) from diffuse reflectance spectroscopy (DRS) measurements. sample thicknesses 1–4 mm, values 3.12–3.14 eV were obtained. With work envisaged a clarification procedure DRS data, since some drawbacks, misconceptions have identified recent literature. particular, widely used practice determining material directly found be inadequate.