title: Improved 800 nm emission of Tm³⁺ sensitized by Yb³⁺ and Ho³⁺ in β-NaYF₄ nanocrystals under 980 nm excitation.
abstract: In vitro and in vivo bioimaging, Yb/Tm doped fluoride nanocrystals (NCs) as nanoprobes have attracted much attention due to their near infrared (NIR) upconversion (UC) emission at 800 nm under NIR 980 nm excitation. Our paper presents a simple and general method which can further improve the intensity of NIR 800 nm emission of Tm³⁺ through adding Ho³⁺ as the second sensitizer of Tm³⁺ in Yb/Tm doped NaYF₄ nanorods. The intensity of the NIR 800 nm emission is demonstrated to increase by up to 3 times along with the adding of Ho³⁺. Experimental data illustrates that the sensitizations of Tm³⁺ by both Yb³⁺ and Ho³⁺ provide a more efficient energy transfer (ET) route for intense 800 nm emission than that by Yb³⁺ alone.
authors.affiliation: School of Basic Sciences, Changchun University of Technology, Changchun 130012, China.
authors.forename: Lili
authors.initials: L
authors.lastname: Wang
authors.forename: Weiping
authors.initials: W
authors.lastname: Qin
authors.forename: Zhenyu
authors.initials: Z
authors.lastname: Liu
authors.forename: Dan
authors.initials: D
authors.lastname: Zhao
authors.forename: Guanshi
authors.initials: G
authors.lastname: Qin
authors.forename: Weihua
authors.initials: W
authors.lastname: Di
authors.forename: Chunfeng
authors.initials: C
authors.lastname: He
mesh_terms: D003460:Crystallization; D007259:Infrared Rays; D008027:Light; D008422:Materials Testing; D053758:Nanoparticles / Q000737:chemistry*; D012542:Scattering, Radiation; D013691:Tellurium / Q000737:chemistry*; D015018:Ytterbium / Q000737:chemistry*
chemical_list: D015018:Ytterbium; D013691:Tellurium