The photoluminescence and magnetic properties of ZnAl2O4:Mn nanocrystals

The single-phase ZnAl2O4 phosphors with various components of Mn2+ dopant were fabricated by using hydrothermal method. The phosphors has been characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), photoluminescence (PL) spectra and vibrating sample magnetometer (VSM). The results of XRD and TEM measurements showed that the resultant nanoparticles were single crystal with octahedral and hexagonal shape, and after annealed, this shape had change. Green emission was observed from doped zinc aluminate with 427 nm excitation. The temperature-dependant PL spectra revealed two emission peaks which exhibited different shifting tendency with a decrease in temperature. The room-temperature hysteresis loops of zinc aluminate nanoparticles showed magnetic behavior, and the magnetism disappeared gradually with the increase of Mn2+ doping contents.

• ZnAl2O4 nanocrystals had hexagonal and octahedral morphology.
• ZnAl2O4 nanocrystals revealed magnetism at room temperature.
• The green emission peak revealed tiny shifts with increasing measurement temperature.