Work function tuning and fluorescence enhancement of hydrogen annealed Ag-doped Al-rich zinc oxide nanostructures using a sol-gel process

The effect of incorporation of Ag doping on the structural, optical, electrical, and fluorescence properties of sol-gel derived Al-rich zinc oxide (ZnO:Al:Ag) nanostructured films was studied. By Ag-doping, the lowest Rλ is blue shifted to RAg/Zn = 2% and finally red shifted for RAg/Zn = 3% due to variation of optical thickness of the film. The Eg of the film slightly decreased to a minimal value with Ag doping, and was found to be about 3.65 eV for RAg/Zn = 1% from its initial value of 3.72 eV (RAg/Zn = 0%). A maximal value of 5.12 eV with Ag doping for RAg/Zn = 1% from its initial value of 4.73 eV for RAg/Zn = 0%. With The defective peak position was blue shifted, with increased Ag-doping, from 536 nm (RAg/Zn = 1%) to 527 nm for RAg/Zn = 2% due to the sizes of the Ag+ and Zn2+ ions. The FL defective peak intensity (ID) in the green region increased with the concentration of Ag used for doping, up to RAg/Zn = 2%. The enhancement in the ID may be due to charge difference between the Zn2+ ions, caused by Ag+ ions.165