Ag-induced surface significant enhanced luminescence of ZnO thin films prepared by sol-gel coating

we have found a simple post-annealing treatment to significantly improve the yellow-green light emission intensity of ZnO thin films. Through excessive doping of silver and appropriate high-temperature annealing treatment, an enhancement of the yellow-green light emission intensity in ZnO thin films by more than 10 times is achieved. The results show that under annealing conditions above 750 degrees C, visible light luminescence exhibits significant enhancement. The presence of Ag elements on the surface of the thin film was confirmed by X-ray diffraction, energy dispersive X-Ray spectroscopy and Raman spectroscopy. The interaction between Ag particles and the surface of ZnO can form localized surface plasmons, which can enhance the yellow-green light emission of ZnO. When Ag particles interact with ZnO, the generation of localized surface plasmons enhances the local electric field, which affects the movement of electrons and the generation of excited states inside the ZnO material, thereby enhancing the yellow-green light emission of ZnO.