Composites of BaAl 2 O 4 :Eu 2+ ,Dy 3+ /organic dye encapsulated in mesoporous silica as multicolor long persistent phosphors based on radiative energy transfer

• Published in: New journal of chemistry Vol. 41; no. 13; pp. 5934 - 5941
• Main Authors: Das, Sourav, Manam, Jairam, Sharma, S. K.
• Format: Journal Article
• Language: English
• Published: 2017
• ISSN: 1144-0546; 1369-9261
• DOI: 10.1039/C7NJ00209B

A multicolor BaAl 2 O 4 :Eu 2+ ,Dy 3+ /dye encapsulated in mesoporous SiO 2 composite long persistent phosphor is developed based on a radiative energy transfer process. Multicolor long persistence luminescence is achieved through radiative energy transfer from BaAl 2 O 4 :Eu 2+ ,Dy 3+ to rhodamine 6G or rhodamine B dye encapsulated in mesoporous silica nanoparticles. BaAl 2 O 4 :Eu 2+ ,Dy 3+ (BAO) is a cyan-emitting long persistent phosphor with high brightness and a long afterglow time. For color tuning, rhodamine 6G dye encapsulated in mesoporous silica (MSNP-Rh6G) or rhodamine B dye encapsulated in mesoporous silica (MSNP-RhB) nanoparticles are mixed with BAO phosphor in different weight ratios to afford BAO/MSNP-Rh6G and BAO/MSNP-RhB composite phosphors. BAO/MSNP-Rh6G shows a long persistent emission with colors varying from cyan to yellow, with similar color tuning observed for BAO/MSNP-RhB. A possible afterglow mechanism is described. The multicolor long persistent phosphors are potentially applicable in displays, bio-imaging, and luminous paints.