title: Waterproof Alkyl Phosphate Coated Fluoride Phosphors for Optoelectronic Materials.
abstract: A facile approach for coating red fluoride phosphors with a moisture-resistant alkyl phosphate layer with a thickness of 50-100 nm is reported. K2 SiF6 :Mn(4+) particles were prepared by co-precipitation and then coated by esterification of P2 O5 with alcohols (methanol, ethanol, and isopropanol). This route was adopted to encapsulate the prepared phosphors using transition-metal ions as cross-linkers between the alkyl phosphate moieties. The coated phosphor particles exhibited a high water tolerance and retained approximately 87 % of their initial external quantum efficiency after aging under high-humidity (85 %) and high-temperature (85 °C) conditions for one month. Warm white-light-emitting diodes that consisted of blue InGaN chips, the prepared K2 SiF6 :Mn(4+) phosphors, and either yellow Y3 Al5 O12 :Ce(3+) phosphors or green β-SiAlON: Eu(2+) phosphors showed excellent color rendition.
authors.affiliation: Department of Chemistry, National Taiwan University, Taipei, 106 (Taiwan).|Institute of Applied Materials Science, Vietnam Academy of Science and Technology, Hochiminh City, 700000 (Vietnam).
authors.forename: Hoang-Duy
authors.initials: HD
authors.lastname: Nguyen
authors.affiliation: Department of Chemistry, National Taiwan University, Taipei, 106 (Taiwan).
authors.forename: Chun Che
authors.initials: CC
authors.lastname: Lin
authors.affiliation: Department of Chemistry, National Taiwan University, Taipei, 106 (Taiwan). rsliu@ntu.edu.tw.|Department of Mechanical Engineering and Graduate Institute of Manufacturing Technology, National Taipei University of Technology, Taipei, 106 (Taiwan). rsliu@ntu.edu.tw.
authors.forename: Ru-Shi
authors.initials: RS
authors.lastname: Liu
keywords: light-emitting diodes; phosphors; photoluminescence; white light