Broadband near ultraviolet random lasing in ZnO 3-D nanowalls

Broadband near ultraviolet (NUV) random laser was achieved by Au nanoparticle loaded ZnO 3-D nanowalls. Au nanoparticle was loaded on ZnO 3-D nanowalls by photo-chemical deposition method using ionic liquid. The optical confinement by the 3-D nanowalls and enhancement of incident light scattering by Au nanoparticle increase the number of resonant modes, and thus leading to a broadband multiple spectrum random lasing. The results demonstrate an important step towards to expand the application scope of NUV laser on medical imaging of cells, solid-state lighting and optical sensor.