Preparation and luminescence of ZnS:Mn nanoparticles on GaN substrates by hydrothermal method

Abstract

ZnS:Mn nanoparticles were prepared on GaN substrates by hydrothermal method. The crystalline structure, surface morphology and optical property were studied in detail. SEM shows that the prepared sample is spherically granular, and each nanoparticle is composed of many small nanoparticles with rough and uneven shape. XRD shows that a blueshift occurs in the diffraction peak (111) of ZnS:Mn compared with that of pure ZnS. The PL spectrum of ZnS:Mn/GaN nanostructure consists of three light emitting bands: the blue light centered at 440 nm, the green light near 500 nm, and the orange light at about 580 nm. The relative integral intensity ratio (blue:green:orange) is 1:0.78:1.01. The PL spectrum covers from blue light to red light (400∼650nm), and the corresponding luminescent color coordinate is (0.3319,0.3196), which is close to standard white light (0.33,0.33). This indicates that it is possible to obtain white light devices by growing ZnS:Mn nanoparticles on GaN substrates.