Enhancement of visible light emission from Tb-doped ZnO nanorods grown on silicon substrate

We report on the enhancement of visible light emission from Tb-doped ZnO nanorods (NRs) fabricated on Si substrates using a simple hydrothermal process without post-thermal annealing. Structural and chemical investigations revealed that the Tb atoms were successfully incorporated into the ZnO crystal lattice without forming Tb-related alloys or impurities. Photoluminescence spectra show the typical double spectral shape of ZnO nanostructures with emission bands in the UV and visible spectral range. The visible light-emission increased linearly with the Tb-content in the solution. The emission mechanism was verified based on the energy band structure of the Tb-doped ZnO NRs.