화학공학소재연구정보센터
Applied Surface Science, Vol.333, 178-185, 2015
Investigation on luminescence enhancement and decay characteristics of long afterglow nanophosphors for dark-vision display applications
Long afterglow SrAl2O4:Eu2+,Dy3+ nanophosphors were synthesized via a facile but effectual auto-combustion technique followed by post-annealing treatment at elevated temperatures. The influence of various fuels during synthesis and thereafter improvement in the luminescence decay characteristics under various illuminant irradiations of long afterglow nanophosphors have been reported. Extensive studies on structural, morphological and luminescent properties of the as-synthesized afterglow nanophosphors have been presented. Powder X-ray diffraction studies confirm the presence of high-purity, single-phase monoclinic nanophosphors. HRTEM investigations confirm the formation of nanophosphors of particle size less than 50 nm. Photoluminescence emission is attributed to the characteristic d-f transition (4f(6)5d(1)-> 4f(7)) of Eu2+ ions and was positioned at 512 nm. As-synthesized nanophosphors exhibit considerable confinement effects resulting into blue shift in emission maxima as compared to their bulk counterparts. The mechanism underlined for long afterglow has been discussed using trapping-detrapping model. The nanophosphor being multifunctional finds many interesting applications including dark-vision display, energy storage, fingerprint detection, in vivo and in vitro biological staining, etc. (C) 2015 Elsevier B.V. All rights reserved.