Luminescence and structure of Eu2+-doped Ba2CaMg2Si6O17

Luminescence and electronic properties of Ba2MgSi2O7:Eu2+: a combined experimental and hybrid density functional theory study

“…2c) yields E a ¼ 0.64 eV, G 0 ¼ 2.15 Â 10 12 Hz and s 0 ¼ 0.74 ms. With the known value of E a , the thermal quenching temperature T 0.5 was estimated to be $435 K, based on the crude relationship between E a and T 0.5 , i.e., E a ¼ T 0.5 / 680 eV. 25 The value of E a is consistent with those reported earlier, 6,10 and is larger than those determined for other Eu 2+ -doped silicates, for example, Cs 2 MgSi 5 O 12 (0.196 eV), 26 BaMgSi 4 O 10 (0.21 eV), 27 Ba 2 CaMg 2 Si 6 O 17 (0.22 eV), 28 CsAlSi 2 O 6 (0.27 eV), 29 Na 2 Ba 2 Si 2 O 7 (0.34 eV), 30 Sr 2 MgSi 2 O 7 (0.40 eV), 31 and Li 2 Ca 2 Si 2 O 7 (0.51 eV). 32 The activation energy E a is supposed to be the energy required to promote an electron from the lowest vibrational level of the rst 4f 6 5d 1 excited state to the bottom of the host conduction band (CB).…”

Synthesis of novel Dy3+ activated Ba2CaZn2Si6O17 phosphors for white light‐emitting diodes

“…Pellyite Ba 2 CaZn 2 Si 6 O 17 was reported to be Ba 2 Ca(Mg, Fe 2+ , Zn, Co) 2 Si 6 O 17 crystallized in a orthorhombic system with space group Cmcm, Z = 4, with lattice parameters a = 15.720 Å, b = 7.146 Å, c = 14.090 Å and V = 1582.96 Å 3 in correspondence with the JCPDS database 32‐0062 . In the Ba 2 CaZn 2 Si 6 O 17 structure, Ba 2+ site is coordinated by 10 O 2− , Ca 2+ site is coordinated by six O 2− where as the Si 4+ and Zn 2+ are both surrounded by four O 2− . The effective ionic radii of cations with different coordination numbers (CNs) were reported by Shannon .…”

Role of site symmetry in photoluminescence spectrum of Eu2+ doped phosphors - A review

“…It has been reported that Ba 2 CaMg 2 Si 6 O 17 :Eu 2+ phosphor was prepared by using a solid state route by Beiling Yuan et al [7]. Ba 2 CaMg 2 Si 6 O 17 :Eu 2+ gives wider excitation spectrum span over 250-500 nm corresponds to 4f→5d transition of Eu 2+ ion [9] maximum at 365 nm indicated in Fig.…”

“…The emission spectrum in these phosphors may be tuned due to variation in the site symmetry or by tuning symmetry in the coordination environment. Eu 2+ doped Ca 3 Mg 3 (PO 4 ) 4 [6], Ba 2 CaMg 2 Si 6 O 17 [7] and Ca 3 Al 2 O 6 [8] oxide based phosphors discussed herein were produced by using solid state route. The employed high temperature during preparation was found suitable for the formation of different site symmetry behaviour in the phosphor.…”