Photoluminescence characteristics of undoped and terbium chloride doped zinc oxide films deposited by spray pyrolysis

Abstract
The photoluminescence characteristics of undoped and TbCl3‐doped zinc oxide films deposited by the spray pyrolysis technique are reported. Undoped films present the characteristic blue‐green emission peak at ∼508 nm observed in single‐crystal and powder ZnO. The TbCl3‐doped films present a luminescence peak at ∼540 nm. The light emission of the doped films decreases with time of exposure of the sample to the excitation light. The phenomenon is interpreted in terms of a simple model in which a competitive process of hole trapping and phototrapping occurs at a radiative recombination center generated by the TbCl3.