title: Unraveling Epitaxial Habits in the NaLnF4 System for Color Multiplexing at the Single-Particle Level.
abstract: We report an epitaxial growth technique for scalable production of hybrid sodium rare-earth fluoride (NaLnF4 ) microcrystals, including NaYF4 , NaYbF4 , and NaLuF4 material systems. The single crystalline nature of the as-synthesized products makes them strong upconversion emission. The freedom of combining a lanthanide activator (Er(3+) or Tm(3+) ) with a sensitizer (Yb(3+) ) at various doping concentrations readily gives access to color multiplexing at the single-particle level. Our kinetic and thermodynamic investigations on the epitaxial growth of core-shell microcrystals using NaLnF4 particle seeds suggest that within a certain size regime it is plausible to exert precise control over shell thickness and growth orientation under hydrothermal conditions.
authors.affiliation: Department of Chemistry, National University of Singapore, 3 Science Drive 3, Singapore, 117543, Singapore.
authors.forename: Yuhai
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: Key Laboratory of Flexible Electronics & Institute of Advanced Materials, Jiangsu National Synergistic Innovation Center for Advanced Materials, Nanjing Tech University, 30 South Puzhu Road, Nanjing, 211816, China. iamlhuang@njtech.edu.cn.
authors.forename: Ling
authors.initials: L
authors.lastname: Huang
authors.affiliation: Department of Chemistry, National University of Singapore, 3 Science Drive 3, Singapore, 117543, Singapore. chmlx@nus.edu.sg.|Institute of Materials Research and Engineering, Agency for Science, Technology and Research, 3 Research Link, Singapore, 117602, Singapore. chmlx@nus.edu.sg.|Center for Functional Materials, NUS (Suzhou) Research Institute, Suzhou, Jiangsu, 215123, China. chmlx@nus.edu.sg.
authors.forename: Xiaogang
authors.identifier: 0000-0003-2517-5790
authors.initials: X
authors.lastname: Liu
keywords: color multiplexing; core-shell structures; epitaxial growth; single crystals; upconversion