Na, Hyejin Woo, Kyoungja Lim, Kipil Jang, Ho Seong 2024-01-20T12:32:15Z 2024-01-20T12:32:15Z 2021-09-01 2013-05 2040-3364 https://pubs.kist.re.kr/handle/201004/128142 We report the systematic control of the morphology of beta-NaYF4:Yb,Er/Tm upconversion nanophosphors (UCNPs) from large spheres (37.9 nm) to rods (length = 60.1 nm, width = 21.5 nm) and from rods to hexagonal prisms (length = 48.8 nm, width = 44.0 nm) or small spheres (14.0 nm) by the use of a surfactant, an additive, and lanthanide doping. Increasing the ratio of oleic acid (OA) to 1-octadecene (ODE) caused a decrease in the size of the UCNPs, and increasing the OA/ODE ratio above a critical value caused the particle shape to change from a sphere to a rod. The length-to-width aspect ratio (AR) of upconversion nanorods (UCNRs) was finely manipulated from 1.28 to 2.80. The rounded tips of the UCNRs were flattened by adding Cl- ions, and the UCNRs changed to hexagonal prisms with a controllable AR depending on the quantity of Cl- ions. Additionally, the morphology of the beta-NaYF4-based UCNPs was controlled by lanthanide doping. The size and AR of the UCNRs decreased with Gd3+ doping, and the UCNRs ultimately transformed into small spheres (14.0 nm) with high monodispersity. Doping with Ce3+ ions also decreased the AR of the UCNRs from 2.80 to 1.27. In addition, highly transparent polymer composites for 3D volumetric displays were fabricated by blending high-AR beta-NaYF4:Yb,Er/Tm UCNRs with polydimethylsiloxane. These composites exhibited bright green and blue upconversion light during excitation with 980 nm light. English ROYAL SOC CHEMISTRY FLUORESCENT NANOPARTICLES NANOCRYSTALS PHASE SHAPE NAYF4 IONS NAYF4-YB,ER PHOSPHORS BRIGHT OXIDE Rational morphology control of beta-NaYF4:Yb,Er/Tm upconversion nanophosphors using a ligand, an additive, and lanthanide doping Article 10.1039/c3nr00080j 1 NANOSCALE, v.5, no.10, pp.4242 - 4251 NANOSCALE 5 10 4242 4251 scie scopus 000318362400031 2-s2.0-84877743350 Chemistry, Multidisciplinary Nanoscience & Nanotechnology Materials Science, Multidisciplinary Physics, Applied Chemistry Science & Technology - Other Topics Materials Science Physics Article FLUORESCENT NANOPARTICLES NANOCRYSTALS PHASE SHAPE NAYF4 IONS NAYF4-YB,ER PHOSPHORS BRIGHT OXIDE morphology control upconversion nanoparticle lanthanide phosphor