Greenish yellow emission from wurtzite structured ZnS:Ce nanophosphor synthesized at low temperature

Publication date: December 2017
Source:Journal of Luminescence, Volume 192
Author(s): K.R. Bindu, E.I. Anila
Cerium doped ZnS nanoparticles were synthesized by aqueous colloidal precipitation method at 70°C and post sintering at 650°C. Their structural, morphological, and photoluminescence properties were investigated. Fourier transform infrared and X-ray diffraction were used to determine chemical bonding and crystal structure of the synthesized nanoparticles. A phase transformation from cubic to wurtzite structure was observed due to sintering at 650°C. Scanning electron microscope revealed that the sintered particles exhibit uneven blocky particles with irregular shape. The band-gap of the nanoparticles was determined from diffuse reflectance spectrum. For the sintered ZnS:Ce nanoparticles when excited at about 350nm, in addition to host UV emission, transitions from ²D to both ²F5/2 and ²F7/2 levels of Ce³⁺ in ZnS lattice were observed resulting in a broad greenish yellow emission band centered at 538nm.

Graphical abstract

http://ift.tt/2tdMlvw