Effect of replacement of Ca by Ln (Ln=Y, Gd) on the structural and luminescence properties of CaWO4:Eu3+ red phosphors prepared via co-precipitation

Energy transfer in Eu^3+ doped scheelites: use as thermographic phosphor

“…The presence of the 313 nm peak in the excitation spectrum of the Eu 3+ emission points to energy transfer between the Gd 3+ and Eu 3+ ions. Apart from that, Gd 3+ has only limited effect on the optical characteristics, which is common in Eu 3+ -Gd 3+ co-doped samples [30,31]. The excitation spectrum is representative for all studied samples, with composition CaGd 2(1-x) Eu 2x (WO 4 ) 4 (x = 0.01, 0.05, 0.1, 0.25, 0.5, 1).…”

Color tuning in thermally stable Sm3+-activated CaWO4nanophosphors

“…In this regard, synthesis and photoluminescence properties of thermally stable Sm 3+ -activated CaWO 4 phosphors have been reported for white light-emitting diodes. A considerable number of approaches have been employed to synthesize CaWO 4 and/or CaWO 4 doped with Ln 3+ with regular particle size and morphological control such as combustion process, 8 solid state reactions, 21,22 Czochralski technique, 23 hydrothermal method, 24,25 co-precipitation process 26 and solvothermal route. 27 However, these chemical routes are not able to produce pure crystalline materials at low temperature.…”

Study of two tungstates Ca0.5Cd0.5WO4 and Ca0.2Cd0.8WO4 by transmission electron microscopy

“…Previously, the two materials CaWO 4 and CdWO 4 were investigated for their potential applications in many fields such as photoluminescence (Hameka et al ., ; Grasser et al ., ; Mikhailik et al ., ; Thongtem et al ., ; Gracia et al ., ; Spassky et al ., ; Zhang et al ., ), microwave applications (Liu et al ., ; Sczancoski et al ., ; Thongtem et al., ), optical fibre scintillator materials (Nikl et al ., ; Nikl et al ., ), humidity sensors and catalysis (Thongtem et al ., ; Lim et al ., ). Among the new potential applications in the field of radiation detection and in the nondestructive testing procedures, it should also be noted that these materials could be used as submicron sensitive elements for detecting noncharged particles (photons and/or neutrons) in sensor devices (Fourmentel et al ., ; Amharrak et al ., ; Taoufyq et al ., ).…”