In this study, we synthesized NaYF-based downshifting nanophosphors (DSNPs), and fabricated DSNP-polydimethylsiloxane (PDMS) composites. Nd ions were doped into the core and shell to increase absorbance at 800 nm. Yb ions were co-doped into the core to achieve intense near-infrared (NIR) luminescence.
View Article and Find Full Text PDFIn this study, heavy-metal-free orange light-emitting ZnSe:Mn/ZnS doped-core/shell (d-C/S) quantum dots (QDs) were synthesized using a nucleation doping strategy. To synthesize high quality d-C/S QDs with high photoluminescence (PL) quantum yield (QY), the Mn concentration was optimized. The resulting ZnSe:Mn(5%)/ZnS d-C/S QDs showed a high PL QY of 83.
View Article and Find Full Text PDFHere, excitation orthogonalized red/green/blue upconversion luminescence (UCL)-based full-color tunable rare-earth (RE) ion-doped upconversion nanophosphors (UCNPs) are reported. The LiREF-based core/sextuple-shell (C/6S) UCNPs are synthesized, and they consist of a blue-emitting core, green-emitting inner shell, and red-emitting outer shell, with inert intermediate and outermost shells. The synthesized C/6S UCNPs emit blue, green, and red light under 980, 800, and 1532 nm, respectively.
View Article and Find Full Text PDFIn this study, Li-based blue- and green-emitting core@shell (C@S) upconversion nanophosphors (UCNPs) and NaGdF-based red-emitting C@S UCNPs were synthesized, and IR-808 dyes were conjugated with the C@S UCNPs to enhance upconversion (UC) luminescence. The surface of the as-synthesized C@S UCNPs, which was originally capped with oleic acid, was modified with BF to conjugate the IR-808 dye having a carboxyl functional group to the surface of the UCNPs. After the conjugation with IR-808 dyes, absorbance of the UCNPs was significantly increased.
View Article and Find Full Text PDFIn this study, intense single-band red-emitting upconversion nanophosphors (UCNPs) excited with 800 nm near-infrared (NIR) light are reported. When a NaYF:Nd,Yb active-shell is formed on the 12.7 nm sized NaGdF:Yb,Ho,Ce UCNP core, the core/shell (C/S) UCNPs show tunable emission from green to red, depending on the Ce concentration under excitation with 800 nm NIR light.
View Article and Find Full Text PDFCore/shell (C/S)-structured upconversion nanophosphor (UCNP)-incorporated polymer waveguide-based flexible transparent displays are demonstrated. Bright green- and blue-emitting Li(Gd,Y)F:Yb,Er and Li(Gd,Y)F:Yb,Tm UCNPs are synthesized via solution chemical route. Their upconversion luminescence (UCL) intensities are enhanced by the formation of C/S structure with LiYF shell.
View Article and Find Full Text PDFACS Appl Mater Interfaces
March 2017
Colloidal quantum dots (QDs) are attractive candidates for future lighting technology. However, in contrast to display applications, the realization of balanced white lighting devices remains conceptually challenging. Here, we demonstrate two-component white light-emitting QD-LEDs with high color rendering indices (CRI) up to 78.
View Article and Find Full Text PDFThe core/shell-structured upconversion nanophosphors (UCNPs) and Cd-free CuInS(2)/ZnS quantum dots (QDs) were synthesized via coprecipitation and hot-injection methods, respectively, and they were applied to near infrared (NIR) photodetectors. The β-NaYF(4):Yb,Er/β-NaYF(4) UCNPs emitted intense visible light peaking at 522, 542, and 656 nm via (2)H(11/2), (4)S(3/2), and (4)F(9/2)→(4)I(15/2) transitions under excitation with 980 nm NIR light. The core/shell UCNPs showed 6.
View Article and Find Full Text PDFACS Appl Mater Interfaces
June 2012
The development of a simple and reliable method for nanoparticles-based ink in an aqueous solution is still a challenge for its inkjet printing application. Herein, we demonstrate the inkjet printing of fractal-aggregated silver (Ag) electrode lines on substrates. Spherical, monodisperse Ag nanoparticles have been synthesized using silver nitrate as a precursor, ethylene glycol as a reducing agent, and polyvinyl pyrrollidone as a capping agent.
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