Effects of preparation on the anti-stokes luminescence of Er-activated rare-earth phosphors

Photon Upconversion in Homogeneous Fluorescence‐based Bioanalytical Assays

“…In addition to upconversion efficiency, the nature of the dopant ions and also in some extent the host material have an influence on the color of the anti‐Stokes photoluminescence emission at visible wavelengths 30 . For example, UCPs doped with Yb 3+ and Er 3+ emit mainly green (510–570 nm) and red (630–680 nm) wavelengths ( 1B); the green emission being typically dominant in fluoride‐based and the red in oxide‐based host lattices 33–35 . Yb 3+ and Tm 3+ doped phosphors, on the other hand, usually produce dominant blue emission (450–500 nm), which is accompanied by a weak red emission in certain host lattices.…”

“…1B); the green emission being typically dominant in fluoride-based and the red in oxide-based host lattices. [33][34][35] Yb 3+ and Tm 3+ doped phosphors, on the other hand, usually produce dominant blue emission (450-500 nm), which is accompanied by a weak red emission in certain host lattices. The dopant ion concentrations [36][37][38][39][40] are also crucial for the relative strengths of two emission colors; the ratio is also influenced by the excitation intensity.…”

Monodisperse upconversion GdF3:Yb, Er rhombi by microwave-assisted synthesis

“…And subsequently, it is concluded that the most efficient infrared-to-visible upconversion phosphors are Yb/Er or Yb/Tm co-doped fluorides, such as hexagonal phase NaYF 4 [6,7], LaF 3 [8,9], and orthorhombic phase YF 3 [10], GdF 3 [11]. Especially in the past few years, the NaYF 4 -based phosphors, as the highest efficient upconversion phosphors, with different morphologies and different dopants have been widely investigated, based on various synthesis procedures.…”

“…Research on upconversion nanocrystals increased exponentially over the past several years (e.g., in 2000, one article on upconversion nanomaterials was published, in 2009, it have been 57) as the extremely attractive prospects for applications of these materials in bioanalytics [ 3 ], (cancer) therapy [ 4 ], and electro-optics [ 5 ]. And subsequently, it is concluded that the most efficient infrared-to-visible upconversion phosphors are Yb/Er or Yb/Tm co-doped fluorides, such as hexagonal phase NaYF 4 [ 6 , 7 ], LaF 3 [ 8 , 9 ], and orthorhombic phase YF 3 [ 10 ], GdF 3 [ 11 ]. Especially in the past few years, the NaYF 4 -based phosphors, as the highest efficient upconversion phosphors, with different morphologies and different dopants have been widely investigated, based on various synthesis procedures.…”

“…They found that the color of the anti-Stokes luminescence of the Yb/Er doped GdF 3 phosphors was controllable by preparation processes, and was associated with the crystal structure of the host lattices. And they gave a dominant green emission when excited by 940 nm infrared light [ 10 ]. In 2006, Fan et al employed a hydrothermal synthesis procedure to produced Yb/Er codoped GdF 3 nanoparticles.…”