title: Novel reddish-orange-emitting BaLa2Si2S8:Eu(2+) thiosilicate phosphor for LED lighting.
abstract: A novel reddish-orange-emitting BaLa2Si2S8:Eu(2+) thiosilicate was prepared in a sealed fused silica ampule and its crystal structure was refined using Rietveld methods. The BaLa2Si2S8:Eu(2+) phosphor is excitable over a broad range from UV to blue (350-450 nm) and generated a reddish-orange broadband emission peaking at 645 nm with a quantum efficiency of ∼24%. The thermal luminescence quenching of BaLa2Si2S8:Eu(2+) was investigated over the range 25 to 150 °C. This phosphor was utilized to incorporate with two commercially available phosphors, blue BaMgAl10O17:Eu(2+) and green (Ba,Sr)2SiO4:Eu(2+), and a near-UV LED chip (405 nm), a white light with Ra of ∼94 was obtained.
authors.affiliation: Phosphors Research Laboratory, Department of Applied Chemistry and Institute of Molecular Science, National Chiao Tung University , Hsinchu 30010, Taiwan.
authors.forename: Szu-Ping
authors.initials: SP
authors.lastname: Lee
authors.forename: Ting-Shan
authors.initials: TS
authors.lastname: Chan
authors.forename: Teng-Ming
authors.initials: TM
authors.lastname: Chen
keywords: LED lighting; photoluminescence; thiosilicate phosphor