Tuning the upconversion photoluminescence lifetimes of NaYF4:Yb3+, Er3+ through lanthanide Gd3+ doping

Abstract

The multiplexing capacity of conventional fluorescence materials are significantly limited by spectral overlap and background interference, mainly due to their short-lived fluorescence lifetimes. Here, we adopt a novel Gd3+ doping strategy in NaYF4 host materials, realized tuning of upconversion photoluminescence (UCPL) lifetimes at selective emissions. Time-correlated single-photon counting (TCSPC), was applied to measure the photoluminescence lifetimes accurately. We demonstrated the large dynamic range of lifetimes of upconversion nanoparticles with good upconversion quantum yields, mainly owing to the dominance of high efficient energy transfer upconversion mechanism. The exceptional tunable properties of upconversion materials allow great potential for them to be utilized in biotechnology and life sciences.

Highly Versatile Upconverting Oxyfluoride-Based Nanophosphor Films

“…We associate the low decay component with the fluoride phase, because lifetimes connected to fluoride lattices are generally longer than those of oxyfluorides. 19 , 72 , 73 Small variations around these average values are observed (see Table 1 ). These are expected considering that photoluminescence dynamics is extremely sensitive to the local environment of the emitters, which can be slightly different, depending on the processing conditions.…”

Yb3+/Er3+ concentration dependent microstructure evolution and green/red emissions of NaYF4:Yb/Er phosphors

“…Diffusion rate of the Fions on the surface increases owing to the decreased charge repulsion. Subsequently, more superfluous Fions capped the c-axis packing planes rather than the aaxis crystal planes due to the lower charge density, which inhibits the rate of the growth along the c-axis crystal planes [15], resulting in an increased speed of NaYbF 4 growth.…”

Surface Plasmon–Photon Coupling in Lanthanide-Doped Nanoparticles

“…Apart from emission intensity, many other features of UCNPs can be tuned for specific applications. For instance, it is possible to vary both emission color and lifetime by changing the doping concentration or by introducing aliovalent dopants. , Additionally, core–shell structure engineering has proven efficacious for controlling emission color . Moreover, aliovalent doping can induce changes in crystal symmetry, resulting in polarized upconversion emission …”