Enhanced visible light absorption by TiO2 film patterned with Ag nanoparticles arrays

Well patterned Ag nanoparticle (NP) arrays were fabricated on TiO2 thin film (TF). Scanning electron microscopy shows Ag NPs distribution on the TiO2 TF surface. The overall Raman scattering intensity increased for the Ag/TiO2 TF system. The enhanced Raman scattering of Ag/TiO2 TF was due to the formation of strong electromagnetic field around the Ag NPs under photon excitation. Optical absorption measurement shows three times enhancement in visible light absorption for the Ag NPs containing samples as compared to bare TiO2 TF. The photoluminescence emission intensity from the Ag NPs/TiO2 TF sample reduced due to the formation of Ag–O complex on the TiO2 surface.