Multifunctionality of GdPO4:Yb3+,Tb3+ nanocrystals – luminescence and magnetic behaviour

Structural features and magnetic behavior of nanocrystalline powders of terbium oxide prepared by the thermal decomposition of terbium acetate in air

“…In fact, sometimes, reported values of x slightly differ from those listed in the leftmost column, and if so, a corresponding remark is provided in the rightmost column of the table. 2 As calculated from the relation µ 2 eff = q×µ 2 (Tb 3+ ) + (1 -q)×µ 2 (Tb 4+ ) , where q is the fraction of Tb 3+ ions out of the total number of Tb cations in the crystalline phase of a Tb oxide, and µ(Tb 3+ ) and µ(Tb 4+ ) are the theoretical magnetic moments of free Tb 3+ and Tb 4+ ions, respectively (see the next footnote). In turn, given a value of x in the chemical formula TbO x of the oxide, q can be calculated, since TbO x = Tb 3+ q Tb 4+ 1-q O 2 -q/2 .…”

“…Terbium oxides find their wide use in many diverse scientific and technological applications [1], [2], [3], [4], such as optical, ceramic, and chemical ones. In optics these compounds have been utilized, for example, by TV manufacturers because Tb 3+ ions are among the most common CRT phosphors [5].…”

Energy migration in YBO 3 :Yb 3+ ,Tb 3+ materials: Down- and upconversion luminescence studies

“…12 shows a comparison of upconversion from different REPO 4 and REBO 3 -based host materials, in which the optimal dopant concentrations were established by us previously [23,54,62,63]. YBO 3 :10%Yb 3+ ,15%Tb 3+ is one from the several studied by us materials which upconversion is very intense, much more efficient than in rare earth phosphates.…”

“…What is more, in Yb 3+ /Tb 3+ system also reverse energy transfer is possible, from Tb 3+ to Yb 3+ ions and the estimated optimal concentrations of these two ions are balance between processes taking place in YBO 3 :Yb 3+ ,Tb 3+ materials. Additionally, such processes as interactions between Tb 3+ ions, multiphonon relaxation and phonon-assisted energy transfer between Tb 3+ and Yb 3+ have also influence on the overall luminescence properties [23,58].…”

“…It is called cooperative energy transfer (CET), where at least two Yb 3+ ions simultaneously transfer energy to one Tb 3+ ion [21][22][23][24][25][26][27]. CET based upconversion occurs when the energy gap between the highest lying component of the ground state of Ln 3+ ion and its first excited state is too large to be bridged by a single, excited Yb 3+ ion.…”