The Luminescent Properties and Synthesis of Sr4Al14O25: Mn4+, Ge4+/Mg2+ Red Nanophosphors

A series of co-doped Ge4+ and Mg2+ ions Sr4Al14O25: Mn4+ red nanophosphors were synthesized by solid-state method. The Sr4Al14O25: Mn4+, Mg2+/Ge4+ phosphors can be excited with both near-UV light and blue light of LED chips effectively. The results showed that the deep red emission peaks of Sr4Al14O25: Mn4+, Mg2+/Ge4+ are located at 654 nm and 665 nm. The optimized concentrations of Mg2+ and Ge4+ in Sr4Al14O25: 0.01Mn(4+), xMg(2+)/Ge4+ were determined to be x = 0.01 and x = 0.02. The emission intensity is increased more than 1.5 times as compared to Sr4Al14O25: 0.01Mn(4+). The lifetimes of Sr4Al14O25: 0.01Mn(4+), 0.01Mg(2+) and Sr4Al14O25: 0.01Mn(4+), 0.02 Ge4+ are similar to 0.926 and 0.927 ms, respectively. The Ge4+ and Mg2+ co-doped Sr4Al14O25: Mn4+ phosphors are good red components for applications in warm white light emitting diodes and plant growth.