Extremely straightforward room temperature co-precipitation method to synthesize cubic KYF4:Yb/Er up-conversion nanoparticles in deionized water-ethanol solution

Abstract

Through extremely facile RT(room temperature) co-precipitation method in mixed deionized water and ethanol solution, cubic KYF 4 :10%Yb/5%Er up-conversion nanoparticles with excellent emission intensity and desirable fluorescence lifetime after annealing under 974 nm pulsed laser excitation have been successfully synthesized. The X-ray powder diffraction pattern has been refined by profile fit in order to obtain accurate lattice parameters. The mean crystallite size and microstrain have been calculated by Williamson-Hall method. Joint effect of crystallite size and microstrain on photoluminescence properties have been studied based on the obtained samples. Green-to-red ratios of the emission spectra and slopes of the emission intensity versus excitation laser power have been investigated. The fluorescence lifetimes of the present samples have also been reported. The extraordinarily facile synthesis route, in environment-friendly solvents, provides a novel proposal to remove some of the obstacles that hinder the up-conversion nanoparticles development.

Simulating excited-state absorption spectra in upconverting lanthanide doped nanoparticles: KY3F10:Er3+

“…We assume that there would not be a significant shift in the diffraction pattern of cubic KErF4 because the ionic radius of the Er 3+ (0.1004 nm) and Y 3+ (0.1040 nm) ion is comparable [26]. A similar comparison was made in previous work [25]. The diffractograms of the α−NaYF4:Yb/Er and β−NaYF4:Yb/Er nanoparticles demonstrate the cubic (space group: Fm3m) and hexagonal (space group: P63/m) phase, compared with standard XRD patterns (JCPDS No.…”

“…Powder XRD patterns of the prepared α and β−phase of KYF4:Yb/Er and NaYF4:Yb/Er nanoparticles are shown in Fig. 1 (a-d b)) [24,25]. The cubic KYF4:Yb/Er diffraction pattern is compared with the standard XRD pattern of cubic KErF4 due to the unavailability of the standard XRD pattern of cubic KYF4 in the database.…”

Assessing the reproducibility and up-scaling of the synthesis of Er,Yb-doped NaYF4-based upconverting nanoparticles and control of size, morphology, and optical properties

“…For the synthesis of UCNPs of different size, morphology, and particle architecture, different methods have been meanwhile developed such as co-precipitation [13][14][15] , hydro(solvo)thermal [16][17][18][19][20][21] , thermal decomposition, and microwave assisted methods [22][23][24] . Up to now, the most facile method for the preparation of monodisperse UCNPs with controlled size and morphology is thermal decomposition.…”

K+-doped P6̄ crystals of NIR-upconverting NaYF4:Yb3+/Ho3+ conform to the ‘strain–intensity’ relationship

“…Notably, no pure hexagonal KYF 4 materials have been reported so far using the thermal decomposition technique presented here. 49…”