Nitridophosphate‐Based Ultra‐Narrow‐Band Blue‐Emitters: Luminescence Properties of AEP(8)N(14):Eu(2+) (AE=Ca, Sr, Ba)

The nitridophosphates AEP(8)N(14) (AE=Ca, Sr, Ba) were synthesized at 4–5 GPa and 1050–1150 °C applying a 1000 t press with multianvil apparatus, following the azide route. The crystal structures of CaP(8)N(14) and SrP(8)N(14) are isotypic. The space group Cmcm was confirmed by powder X‐ray diffraction. The structure of BaP(8)N(14) (space group Amm2) was elucidated by a combination of transmission electron microscopy and diffraction of microfocused synchrotron radiation. Phase purity was confirmed by Rietveld refinement. IR spectra are consistent with the structure models and the chemical compositions were confirmed by X‐ray spectroscopy. Luminescence properties of Eu(2+)‐doped samples were investigated upon excitation with UV to blue light. CaP(8)N(14) (λ (em)=470 nm; fwhm=1380 cm(−1)) and SrP(8)N(14) (λ (em)=440 nm; fwhm=1350 cm(−1)) can be classified as the first ultra‐narrow‐band blue‐emitting Eu(2+)‐doped nitridophosphates. BaP(8)N(14) shows a notably broader blue emission (λ (em)=417/457 nm; fwhm=2075/3550 cm(−1)).