A novel broad-band red K2MgSiO4:Eu2+ phosphor and defect-induced tunable emission from red to yellow

Tunable emission in red phosphors is a challenge for the application of wLED. Herein, we reported a new Eu2+ doped oxide based red K2MgSiO4:Eu2+ phosphor. Under excitation at 319 nm, the K2MgSiO4: Eu2+ phosphor exhibits a broad band red emission peaking at 648 nm with FWHM similar to 231 nm. The structural and spectral analyses suggest that Eu2+ occupy K1/K3O6 sites and K2/K4O8 sites to form two Gaussian fitting emissions at 732 nm and 629 nm, respectively. To achieve tunable emission, reducing the Si content is attempted in K2MgSi1-yO4: Eu2+. As the Si content decreases from y = 0 to y = 0.04, the emission spectrum shows a blue shift from 648 nm to 523 nm. Therefore, defect-induced color-tunable phosphors from red to yellow are obtained through reducing Si content in the host. This study aims to provide a new research method to guide the development of Eu2+ doped oxide based red phosphors and design idea to obtain tunable emission of phosphors. Moreover, the defectinduced photoluminescence tuning strategy is universal to most luminescent materials.

Automated summary

This study reports a new red K2MgSiO4:Eu2+ phosphor with tunable emission by reducing the Si content. The research provides a new research method to guide the development of Eu2+ doped oxide based red phosphors and design idea to obtain tunable emission of phosphors. Moreover, the defect-induced photoluminescence tuning strategy is universal to most luminescent materials.