Solid state-synthesized lanthanum orthovanadate (LaVO4) Co-doped with Eu as efficient photoluminescent material

A bacterial cellulose-based LiSrVO4:Eu3+ nanosensor platform for smartphone sensing of levodopa and dopamine: point-of-care diagnosis of Parkinson's disease

“…51 Finally, the contribution at 519.7 eV can be related to V-OH when moisture is in the sample. 52,53 Fig. 3C shows the XPS spectrum of O 1s, which can be converted into 5 peaks at binding energies of 529.5 eV, 530.4 eV, 531.34 eV, 532.33 eV, and 533.43 eV.…”

Comparative studies of upconversion luminescence and optical temperature sensing in Tm3+/Yb3+ codoped LaVO4 and GdVO4 phosphors

“…The diffraction peaks were well matched with the typical monoclinic phase of LaVO 4 (JCPDS No: 01-070-2392) with the space group P2 1 /n ( 14) and tetragonal phase of GdVO 4 (JCPDS No: 017-0260) with space group I 41 /amd (141). 15,32 There were no traces of impurity phases present in the recorded patterns. Here it is interesting to note that both the phosphors were prepared under similar environmental conditions but both have resulted different crystal phases.…”

“…Previous reports indicate that monazite type LaVO 4 is an indirect band gap material while tetragonal GdVO 4 is a direct band gap material. 15,35,39,40 For estimation of band gap values, the plots of [F(R)hn] 1/n versus hn for indirect and direct band gap transitions are shown in Fig. 2(b).…”

“…The zircon type yttrium orthovanadate (YVO 4 ) and gadolinium orthovanadate (GdVO 4 ) have been studied for upconversion emission and strong upconversion luminescence is noted in these hosts. 15,16 The LaVO 4 host however, is found to exist in two polymorphs, either tetragonal (t-) zircon type structure or monoclinic (m-) monazite type structure depending upon the reaction methods. 14 Lanthanide ions with a larger ionic radius prefer to choose monazite structure because of its higher oxygen coordination number (9).…”

“…14 Lanthanide ions with a larger ionic radius prefer to choose monazite structure because of its higher oxygen coordination number (9). 15 On the line of YVO 4 and GdVO 4 hosts it is expected that LaVO 4 can be a good candidate for strong upconversion emission which is also revealed by Shao et al 17 It is feasible to create multi-colored emission by doping with various rare earth (Ln 3+ ) ions, such as red from Eu 3+ , green from Er 3+ , and blue from Tm 3+ ions. The LaVO 4 is substantially less expensive and is based on a resource that is far more abundant than Y.…”