Zn Doping Induced Band Gap Widening of Ag2O Nanoparticles

The present investigation widens the narrow bandgap of Ag₂O to make it a semiconductor with more attractive properties. A typical hydrothermal synthesis procedure was used to prepare Zn doped Ag₂O nanoparticles. The X-ray diffraction analysis of the prepared powder samples showed that the lattice parameters of Ag₂O increase with doping, indicating the occupation of interstitial positions by the dopant atoms. Density functional theory calculations also demonstrated the expansion of the Ag₂O crystal lattice with the dopant at an interstitial location. The bandgap of the Ag₂O increases to 1.65 eV for 5-mole percent doping. The doped Ag₂O nanoparticles photocatalytically degrade methyl orange under aerobic visible light conditions. It appears that the rise in the percentage of higher valence Zn doping converts the originally p-type to an n-type semiconductor.