title: Lanthanide doped Bi2O3 upconversion luminescence nanospheres for temperature sensing and optical imaging.
abstract: Water-soluble lanthanide (Ln(3+)) doped Bi2O3 nanospheres have been successfully prepared through a solid-state-chemistry thermal decomposition process. The nanospheres exhibit intense upconversion luminescence (UCL) by doping the Ln(3+) (Ln = Yb, Er/Ho/Tm) ions into the Bi2O3 host matrix under 980 nm excitation. The ratio of red/green emission of Bi2O3:Yb(3+)/Er(3+) nanospheres exhibits a significant change as the calcination temperature increases and the value could reach 105.6. Moreover, the UCL of Bi2O3:Yb(3+)/Tm(3+) nanospheres are temperature-sensitive, where the intensity ratios of 799 and 808 nm emissions increase monotonously with temperature. The MTT assay reveals that Bi2O3:Yb(3+)/Tm(3+) nanospheres exhibit good biocompatibility by grafting citric acid molecules on the surface. The application possibility of Bi2O3:Yb(3+)/Tm(3+) nanospheres as bioprobes for optical imaging in vivo is also confirmed by the high-contrast photoluminescence images between the background and the UCL imaging area.
authors.affiliation: State Key Laboratory of Rare Earth Resource Utilization, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, 5625 Renmin Street, Changchun 130022, China. fengj@ciac.ac.cn hongjie@ciac.ac.cn.
authors.forename: Pengpeng
authors.initials: P
authors.lastname: Lei
authors.forename: Xiuling
authors.initials: X
authors.lastname: Liu
authors.forename: Lile
authors.initials: L
authors.lastname: Dong
authors.forename: Zhuo
authors.initials: Z
authors.lastname: Wang
authors.forename: Shuyan
authors.initials: S
authors.lastname: Song
authors.forename: Xia
authors.initials: X
authors.lastname: Xu
authors.forename: Yue
authors.initials: Y
authors.lastname: Su
authors.forename: Jing
authors.initials: J
authors.lastname: Feng
authors.forename: Hongjie
authors.initials: H
authors.lastname: Zhang