New Silicate Phosphors for a White LED

Luminescent properties of Eu2+ and Ce3+ ions in strontium litho-silicate Li2SrSiO4

“…They consist of a broad band with a maximum at about 241 nm and a number of relatively narrow bands at the longer wavelengths. It is evident that the intense band is caused by the charge transfer (CT) transition from the oxygen 2p states to the empty states of the Eu 3 + 4f 6 -configuration, while the weaker ones are due to the 4f 6 -4f 6 transitions of Eu 3 + ions. The onset of the CT band at 290 nm (4.27 eV) is attributed to the energy threshold of O 2p-Eu 4f transitions.…”

“…This stimulates the search for new luminescent materials for LEDs. In recent years, several materials of silicate family, such as Sr 3 [6,[9][10][11], have been presented as promising phosphors for white LEDs. Among these series, materials of composition Li 2 SrSiO 4 :Eu 2 + (Ce 3 + ) gained special attention because of their favorable luminescent properties and a weak thermal quenching of luminescence.…”

“…Among these series, materials of composition Li 2 SrSiO 4 :Eu 2 + (Ce 3 + ) gained special attention because of their favorable luminescent properties and a weak thermal quenching of luminescence. Several groups of authors have studied the luminescent properties of Eu 2 + ions in Li 2 SrSiO 4 upon excitation in the 240-550 nm region [6,[9][10][11]. It was found that Eu 2 + -doped Li 2 SrSiO 4 shows a broad band emission with a maximum at about 570 nm.…”

ZnWO4:Eu3+ nanorods: A potential tunable white light-emitting phosphors

“…Phosphors converted white light-emitting diodes (pc-WLEDs) are considered as the next generation solid state lighting, the commercial available pc-WLEDs are mostly fabricated by combining blue LED with a yellow emitting phosphor (YAG:Ce) [5,6]. However, the lack of red emitting component results in low color rendering index (CRI) [7]. The commonly alternative way is to employ an ultraviolet (UV) LED chip as the excitation light source with different color phosphors [8,9].…”

Luminescence of Eu2+ ions in alkaline earth dilithiosilicates

“…Alkaline-earth (AE) silicates doped with Eu 2+ are some of the most important and promising materials for creating LEDs. This is due to their high luminescence efficiency upon excitation in the range 360-470 nm and comparatively weak thermal quenching of the emission up to 450 K [2][3][4]. The potential of using AE silicates of composition MLi 2 SiO 4 (M = Ca, Sr, Ba) doped with Eu 2+ as luminophores for creating LEDs with white emission was reported [3][4][5][6][7].…”