title: Improved Near-Infrared Up-Conversion Emission of Tm3+ Sensitized by Yb3+ and Ho3+ in LuF3 Nanocrystals.
abstract: In the present work, mono-disperse and uniform orthorhombic lutetium fluoride (LuF3) nanocrystals with an average size of about 35 nm have been successfully synthesized by a simple ionothermal method without any template. The infrared (IR) to visible up-conversion (UC) photoluminescence of LuF3 doped with Yb3+, Tm3+, and Ho3+ under 980 nm excitation was systemically studied. The intensity of near infrared (NIR) to visible up-conversion emission of Tm3+ was improved efficiently by adding Yb3+ and Ho3+ in LuF3, especially for the broad NIR emission band located at 812 nm. Meanwhile, compared to the Yb3+ and Tm3+ co-doped LuF3, the ratio of red to green emission in the Yb3+, TmS+, and HoS+ co-doped LuF3 changed greatly, and a bright yellowish-green emission was observed under 980 nm laser excitation. It shows that Yb3+, Tm3+ and Ho3+ co-doped LuF3 nanocrystals provided a potential application in vitro and in vivo bio-imaging, color displays and optical storage.
authors.forename: Xuhui
authors.initials: X
authors.lastname: Xu
authors.forename: Yumei
authors.initials: Y
authors.lastname: Wu
authors.forename: Wenjuan
authors.initials: W
authors.lastname: Bian
authors.forename: Xue
authors.initials: X
authors.lastname: Yu
authors.forename: Buhao
authors.initials: B
authors.lastname: Zhang
authors.forename: Qianyue
authors.initials: Q
authors.lastname: Li
authors.forename: Jianbei
authors.initials: J
authors.lastname: Qiu
authors.forename: BiTao
authors.initials: B
authors.lastname: Liu