title: Photoluminescence profiles and fast/slow annealing effects of Eu(III)/Tb(III)-codoped silica phosphor materials.
abstract: A silica (SiO2) nanoparticle matrix was codoped with luminescent Eu(III) and Tb(III) ions using a modified Stöber method. The effects of fast and slow thermal annealing on photoluminescence profile imaging were examined. Slow annealing treatment suppressed more quenching sites than fast thermal annealing to further increase the photoluminescence signals. The photoluminescence signals observed between 450 and 720 nm were assigned to the (5)D(0)  → (7)F(J) (J = 0,1,2,3,4) of Eu(III) and the (5)D(4)  → (7)F(J) (J = 6,5,4,3) transitions of Tb(III). Photoluminescence was largely sensitized by indirect excitation and was much stronger than that generated by direct excitation. The Eu(III) and Tb(III) ions were doped at lower symmetry sites in the silica matrix.
authors.affiliation: School of Chemistry and Biochemistry, Yeungnam University, Gyeongsan, Gyeongbuk, 38541, South Korea.
authors.forename: Hee Jung
authors.initials: HJ
authors.lastname: Yoon
authors.affiliation: School of Chemistry and Biochemistry, Yeungnam University, Gyeongsan, Gyeongbuk, 38541, South Korea.
authors.forename: Young In
authors.initials: YI
authors.lastname: Choi
authors.affiliation: Department of Chemistry, Chungnam National University, Daejeon, 34134, South Korea.
authors.forename: Jun-Gill
authors.initials: JG
authors.lastname: Kang
authors.affiliation: School of Chemistry and Biochemistry, Yeungnam University, Gyeongsan, Gyeongbuk, 38541, South Korea.
authors.forename: Youngku
authors.initials: Y
authors.lastname: Sohn
mesh_terms: D005063:Europium / Q000737:chemistry*; D049449:Luminescence; D053758:Nanoparticles / Q000737:chemistry; D055668:Photochemical Processes; D012822:Silicon Dioxide / Q000737:chemistry*; D013725:Terbium / Q000737:chemistry*; D013997:Time Factors
chemical_list: D013725:Terbium; D005063:Europium; D012822:Silicon Dioxide
keywords: Eu(III); Tb(III); annealing; photoluminescence; silica