Frequency upconversion in catechin assisted $$\hbox {LaF}_{3}$$ LaF 3 : $$\hbox {Yb}^{3+}$$ Yb

Abstract

Yb 3+-Er 3+ codoped lanthanum upconverting nanostructures with varying concentration of dopants have been synthesized by catechin method. The prepared upconverting nanostructures were characterized through XRD, TEM, XPS, NIR absorption, TGA and DSC analysis. TEM study confirms the formation of squareshaped nanoplates with size less than 100 nm. XPS peaks around 830-854 eV further reveal the formation of LaF 3 in the prepared samples. Frequency upconversion spectra from the developed nanostructures corresponding to the 2 H 11/2 , 4 S 3/2 → 4 I 15/2 and 4 F 9/2 → 4 I 15/2 transitions upon 980 nm excitation are reported. Enhancement in the upconversion emission of catechin-based lanthanum nanostructures has been observed when compared with that prepared by ammonium din -octadecyldithiophosphate (AODTP) method.

LaF3 Doped Co3O4 Mesoporous Nanomaterials with Hierarchical Structure for Enhanced Triethylamine Gas Sensing Performances

“…32 The peaks located at 837.9 eV and 842.2 eV, respectively, are assigned to the corresponding 3d 5/2 lines, indicating the presence of the La-F bond. Meanwhile, the peaks observed at 854.7 eV and 859.0 eV, respectively, are attributed to the corresponding 3d 3/2 lines, 36 the energy gap between the two sets being approximately 16.8 eV. The presence of the strong F 1 s peak and the La 3d peaks further confirmed the formation of the LaF 3 nanocrystalline phase in La-Co 3 O 4 .…”

“…32 The presence of the La-O bond on the La-Co 3 O 4 surface may result from the high mobility of the Fions, which leads to numerous defects on the La-Co 3 O 4 surface, thereby favoring O 2 adsorption and resulting in the formation of the La-O bonds. 32,36 Figure 3d To further investigate the physicochemical properties of the surfaces of the two materials, N 2 adsorption-desorption measurements of La-Co 3 O 4 and N-Co 3 O 4 were conducted. The corresponding BJH pore size distributions are shown in Fig.…”

Role of synthesis of upconversion nanoparticles towards surface modification and photocatalysis

“…Here, Er 2 O 3 was selected as the primary rare earth oxide, as it has comparatively high upconversion efficacy among the other rare earth oxides, and the concentration was kept constant at 2 at% [30,[34][35][36][37]. Yb 2 O 3 was chosen as the sensitizer in combination with Er 2 O 3 , and the concentration was varied from 5, 10 and 20 at%.…”