NaBaLa2(PO4)3: A novel host lattice for Sm3+-doped phosphor materials emitting reddish-orange light

- Novel eulytite-type NaBaLa2(PO4)3: Sm3+ materials were firstly designed and synthesized.
- The crystal structure and luminescent properties of NaBaLa2(PO4)3: Sm3+ samples were systematically investigated.
- The NaBaLa2(PO4)3: Sm3+ phosphor shows good thermal stability and acceptable emission efficiency.

A series of reddish orange light-emitting NaBaLa2(PO4)3: Sm3+(NBLP:Sm3+) phosphors are designed and synthesized in this work for the first time. The crystal structure of NaBaLa2(PO4)3(NBLP) has been studied by the Rietveld refinement analysis, which shows that the NBLP belongs to eulytite-type orthophosphate. Luminescence properties of NBLP:Sm3+ phosphors were investigated in detail, including excitation and emission spectra, concentration quenching, fluorescence decay, Inokuti-Hirayama (I-H) model analysis, etc. The Commission Internationale de L'Eclairage (CIE) coordinates exhibited a shift slightly from reddish-orange (0.5782, 0.4171) to orange (0.5605, 0.4312) with the increase of Sm3+ concentration. In addition, the NBLP:Sm3+ phosphor shows good thermal stability and acceptable quantum efficiency. From the obtained results, the prepared phosphor NBLP: Sm3+ can be demonstrated as a potential orange-red luminescent material.

The SEM mapping images of Na, Ba, La, O, P, and Sm on the surface of the selected area for NaBaLa1.89(PO4)3:0.11Sm3+ sample.601