Tunable broadband upconversion luminescence from Yb3+/Mn2+ co-doped dual-phase glass ceramics

Site-Selective Occupation for Broadband Upconversion Luminescence in Ca3Y(GaO)3(BO3)4:Yb3+,Mn2+ Phosphors

“…The UC luminescence dynamics of the CYGB:0.01Yb 3+ ,0.45Mn 2+ is also investigated through the decay curves monitored at 600 nm. As shown in Figure b, the decay curve is well fitted by a double exponential function, which indicates that the decay process is composed of two decay channels with different decay rates: , where I ( t ) and I 0 are the intensity at time t and initial time 0, A 1 and A 2 are constants, τ 1 and τ 2 are the fast and slow decay lifetime of Mn 2+ ions, respectively. With these obtained parameters, the average lifetime τ* can be reckoned by the formula below: The calculated average lifetimes of CYGB:0.01Yb 3+ ,0.45Mn 2+ are about 3.06 ms, which is common for the decay lifetime of Mn 2+ in millisecond magnitude .…”

“…10 This limitation has not been broken until Rodri ́guez reports the green UC luminescence in LaMgAl 11 O 19 :Yb 3+ ,Mn 2+ system at room temperature (RT). 18,19 From then on, more and more studies on Yb 3+ and Mn 2+ ions codoped UC materials such as BaB 8 O 13 , 20 MgGa 2 O 4 , 21 CaO, 22 and oxyfluoride glass− ceramics 23 are reported, especially the intense and tunable UC emission of Mn 2+ in fluoride perovskite nanocrystals and its abnormal emission wavelength into NIR region. 24−27 All of the previous results have agreed well with the conclusions that the crystal structure of host lattice, the site occupancy of Mn 2+ ions as well as the connectivity of as-formed polyhedrons have a critical effect on the UC behaviors of Mn 2+ .…”

“…And then researches have been carried out on different compounds in manganese halide system, and a new model of Yb 3+ –Mn 2+ pairs is proposed to explain the observed UC emission. − It is worth noting that the UC luminescence in such an Mn-enriched system is available only at cryogenic temperature due to the dramatically enhanced nonradiative transfer probability with the rising temperature . This limitation has not been broken until Rodríguez reports the green UC luminescence in LaMgAl 11 O 19 :Yb 3+ ,Mn 2+ system at room temperature (RT). , From then on, more and more studies on Yb 3+ and Mn 2+ ions codoped UC materials such as BaB 8 O 13 , MgGa 2 O 4 , CaO, and oxyfluoride glass–ceramics are reported, especially the intense and tunable UC emission of Mn 2+ in fluoride perovskite nanocrystals and its abnormal emission wavelength into NIR region. − All of the previous results have agreed well with the conclusions that the crystal structure of host lattice, the site occupancy of Mn 2+ ions as well as the connectivity of as-formed polyhedrons have a critical effect on the UC behaviors of Mn 2+ . In order to obtain highly efficient UC broadband emission from TM activators at RT, it is still urgent to make more effort into the development of new Mn 2+ -doped UC materials.…”

Up-conversion emission in transition metal and lanthanide co-doped systems: dimer sensitization revisited

“…Because of the ability to control both the intensity and colour of Ln UC, TM co-doping is praised as a solid strategy for optimizing UC emission with foreseen applications in displays, lasers, photonics 17 , bioimaging 16 , 25 , solar cells 26 thermometry 9 , 27 – 29 , pH sensor 15 . Despite the increased interest in TM, Ln UC systems, a detailed understanding of the underlying mechanism, which is mandatory for designing new materials, is not available.…”

Fluorescence regulation derived from Eu3+ in miscible-order fluoride-phosphate blocky phosphor

“…At the same time, the utilization of inorganic precursor glass as an encapsulant has attracted growing attention which has more advantages than organic resin such as excellent aging resistance and heat resistance. The precursor glass mixed with various phosphors to produce multi-color emissions is an effective method to obtain WLED [21][22][23][24][25]. However, the phenomenon of photon reabsorption between phosphors causes the decrease of the luminescence efficiency [26,27].…”