X-ray photoemission studies of RE-doped NaZr₂(PO₄)₃ phosphor

The optical properties of the phosphates have captured the attention of researchers all over the world owing to their remarkable properties such as low sintering temperature, high luminescent efficiency, broad bandgap, and high chemical stability. XPS is a surface-sensitive analytical technique that may be used to investigate the elemental composition, oxidation state, and chemical bonding. XPS survey scan reveals the presence of Na, Zr, P, O, Sm and Dy on the surface of the synthesized samples (NaZr₂(PO₄)₃:Sm³⁺ and NaZr₂(PO₄)₃:Eu³⁺). For charge shift correction C 1 s peak is used as reference peak and the presence of C is mainly due to the exposure of sample in the air prior to the XPS measurements. The core level scan of Sm 3d and Eu 3d details the presence of Sm and Eu in 3+ valance state. Also the core level scan for Na ls, Zr 3d, O ls and P 2p are studied. (author)