Co-precipitation synthesis and photoluminescence properties of K2GdZr (PO4)3:Eu3+—a deep red luminomagnetic nanophosphor

Nanoparticles of Eu3+ activated K2GdZr(PO4)3 has been successfully synthesized by controlled inclusive co-precipitation method in high alkaline environment to enable complex crystalline phase formation. Much enhanced deep red luminescence, broadened emission bands with unusually prominent 5D0–7F4 transition at 699 nm are defining characteristics of the nanoparticles compared to bulk counterpart synthesized by solid state reaction route. Among various excitation pathways such as charge transfer from O2−–Eu3+, Gd3+–Eu3+, the direct excitation of Eu3+ at 394 nm is the most effective as revealed by photoluminescence and time resolved studies. Occurrence and variation of superparamagnetism in undoped and Eu3+ doped nanoparticles indicate the role of unpaired 4f electron spin of Gd3+ in making the nanoparticles superparamagnetic. A room temperature cost effective synthesis process of Eu3+ doped multimetallic complex phosphate supermagnetic nanophosphor can pave way for applications requiring such functionality.