Energy transfers between Sm3+ and Eu3+ in YPO4, LaP5O14 and LaP3O9 phosphates. Potential quantum cutters for red emitting phosphors

Luminescence spectroscopy and energy level location of lanthanide ions doped in La(PO3)3

“…The inorganic compounds with general formula Ln(PO 3 ) 3 (Ln¼La to Lu and Y) belong to the broader class of phosphate materials which have been extensively investigated because of a suitable absorption in the VUV region, a wide band gap together with a high chemical stability, and the relative simplicity of powder synthesis [1,2]. The Ce 3 þ luminescence in Ce(PO 3 ) 3 was studied by Ternane et al [3], and in Lu(PO 3 ) 3 by Yuan et al [4].…”

“…Much attention has been paid to the energy migration and transfer processes in Ln-based phosphate compounds [9][10][11]. Ln(PO 3 ) 3 (Ln¼La to Lu and Y) is one of the complex phosphates, which can adopt two different crystal structures depending on the ionic radius of the Ln ion.…”

Thermal loading induced near-infrared broadband upconversion emission of Sm3+-doped β-NaYbF4 nano-phosphors

“…Such a spectral characteristic implies that the high-energy states of Sm 3 þ ions are very difficult to be populated through a UC process, even in low-energy fluoride host lattice. Thus, the down-conversion luminescence of Sm 3 þ ions is usually reported in oxybromide, phosphates, and glass materials [14][15][16][17]. Notably the cooperative UC process of Yb 3 þ -Yb 3 þ ion pairs [18] may become active in the b-NaYbF4 crystals due to high Yb 3 þ concentration, which is expected to sensitize Sm 3 þ ions through a cooperative energy transfer process of Yb 3 þ -Yb 3 þ ion pairs.…”

Luminescence properties of Sm3+ doped YPO4: Effect of solvent, heat-treatment, Ca2+/W6+-co-doping and its hyperthermia application

“…15 The origin of luminescent properties is from the intra 4f and 4f-5d transitions of different kinds of rare earth ions, especially the intra 4f transitions which are less influenced by the surrounding ligands owing to the shielding of the 4f orbital by the outer 5s and 5p orbitals. Though [16][17][18][19][20][21][22][23][24] The lowest excited level of Sm 3+ is 4 G 5/2 and it has three main emitting levels 6 H j (j = 5/2, 7/2 and 9/2) located at 564, 601 and 645 nm, respectively, which gives reddish-orange emission. 23,24 However, when wet a Author to whom correspondence should be addressed.…”

“…Though [16][17][18][19][20][21][22][23][24] The lowest excited level of Sm 3+ is 4 G 5/2 and it has three main emitting levels 6 H j (j = 5/2, 7/2 and 9/2) located at 564, 601 and 645 nm, respectively, which gives reddish-orange emission. 23,24 However, when wet a Author to whom correspondence should be addressed. 25,26 This can lead to a decrease in emission intensity from the rare earth ion.…”