title: Tuning NaYF₄ Nanoparticles through Alkaline Earth Doping.
abstract: Phase and size of lanthanide-doped nanoparticles are the most important characteristics that dictate optical properties of these nanoparticles and affect their technological applications. Herein, we present a systematic study to examine the effect of alkaline earth doping on the formation of NaYF₄ upconversion nanoparticles. We show that alkaline earth doping has a dual function of tuning particle size of hexagonal phase NaYF₄ nanoparticles and stabilizing cubic phase NaYF₄ nanoparticles depending on composition and concentration of the dopant ions. The study described here represents a facile and general strategy to tuning the properties of NaYF₄ upconversion nanoparticles.
authors.affiliation: Department of Physics and Materials Science, City University of Hong Kong, 83 Tat Chee Avenue, Hong Kong. zjuchenxian@gmail.com.
authors.forename: Xian
authors.initials: X
authors.lastname: Chen
authors.affiliation: Department of Physics and Materials Science, City University of Hong Kong, 83 Tat Chee Avenue, Hong Kong. dengpeng@cityu.edu.hk.
authors.forename: Dengfeng
authors.initials: D
authors.lastname: Peng
authors.affiliation: Department of Physics and Materials Science, City University of Hong Kong, 83 Tat Chee Avenue, Hong Kong. fwang24@cityu.edu.hk.|City University of Hong Kong Shenzhen Research Institute, Shenzhen 518057, China. fwang24@cityu.edu.hk.
authors.forename: Feng
authors.initials: F
authors.lastname: Wang
keywords: impurity doping; nanoparticles; phase transformation; upconversion