Optical band gap, photocatalysis, surface structures and depth profile properties of Cu₂Se nanostructured thin films

Abstract The optical behaviour, stoichiometry, surface configuration of Cu 2 Se nanostructured thin layers prepared at different reaction times by the chemical process has been considered. band gap deposited films decreases from 2.92 eV to 2.08 for first transition and 2.18 1.2 second transition. In addition, it was shown that Urbach energy is independent film thickness, tail values localized states decreased 1.15 0.33 eV. It found concentration Cu: remains approximately constant across depth higher deposition time. degradation efficiency 98% achieved Congo red Cu2Se optimal condition which make a good candidate organic dye. From these measurements controlling energy, can find application in solar cell application.