New Series of Red-Light Phosphor Ca<sub>9−</sub><i><sub>x</sub></i>Zn<i><sub>x</sub></i>Gd<sub>0.9</sub>(PO<sub>4</sub>)<sub>7</sub>:0.1Eu<sup>3+</sup> (<i>x</i> = 0–1)
Yury Yu. Dikhtyar,
Dmitry A. Spassky,
Vladimir A. Morozov,
Sergey N. Polyakov,
Valerya D. Romanova,
Sergey Yu. Stefanovich,
Dina V. Deyneko,
Oksana V. Baryshnikova,
Ivan V. Nikiforov,
Bogan I. Lazoryak
Affiliations
Yury Yu. Dikhtyar
Chemistry Department, Lomonosov Moscow State University, 119991 Moscow, Russia
Dmitry A. Spassky
Skobeltsyn Institute of Nuclear Physics, Lomonosov Moscow State University, 119991 Moscow, Russia
Vladimir A. Morozov
Chemistry Department, Lomonosov Moscow State University, 119991 Moscow, Russia
Sergey N. Polyakov
Technological Institute for Superhard and Novel Carbon Materials, Troitsk, 108840 Moscow, Russia
Valerya D. Romanova
Chemistry Department, Lomonosov Moscow State University, 119991 Moscow, Russia
Sergey Yu. Stefanovich
Chemistry Department, Lomonosov Moscow State University, 119991 Moscow, Russia
Dina V. Deyneko
Chemistry Department, Lomonosov Moscow State University, 119991 Moscow, Russia
Oksana V. Baryshnikova
Chemistry Department, Lomonosov Moscow State University, 119991 Moscow, Russia
Ivan V. Nikiforov
Chemistry Department, Lomonosov Moscow State University, 119991 Moscow, Russia
Bogan I. Lazoryak
Chemistry Department, Lomonosov Moscow State University, 119991 Moscow, Russia
In this study, a new series of phosphors, Ca9−xZnxGd0.9(PO4)7:0.1Eu3+ (x = 0.00–1.00, step dx 0.05), was synthesized, consisting of centro- and non-centrosymmetric phases with β-Ca3(PO4)2-type structure. Crystal structures with space groups R3c (0.00 ≤ x R3¯c (x > 0.8) were determined using X-ray powder diffraction and the method of optical second harmonic generation. In the region 0.35 ≤ x ≤ 0.75, phases R3c and R3¯c were present simultaneously. Refinement of the Ca8ZnGd(PO4)7 crystal structure with the Rietveld method showed that 71% of Gd3+ ions are in M3 sites and 29% are in M1 sites. A luminescent spectroscopy study of Ca9−xZnxGd0.9(PO4)7:0.1Eu3+ indicated the energy transfer from the crystalline host to the Gd3+ and Eu3+ luminescent centers. The maximum Eu3+ luminescence intensity corresponds to the composition with x = 1.
