Ionic Liquid Based Approach to Luminescent LaPO₄:Ce,Tb Nanocrystals: Synthesis, Characterization and Application

Abstract

LaPO 4 :Ce,Tb as a nanoscale phosphor is prepared via a microwave-accelerated synthesis in ionic liquids. The underlying approach results in non-agglomerated nanocrystals, 9-12 nm in size, and exhibiting quantum yields of 70 % (Tbrelated emission) and 90 % (Ce/Tb-related emission). Based on the underlying concept of synthesis, application-oriented aspects are focused. Driven by the addition of oleylamine, first, phase transfer from the polar phase of synthesis to non-

LaPO4:Ce,Tb and YVO4:Eu nanophosphors: Luminescence studies in the vacuum ultraviolet spectral range

“…This method was described in detail elsewhere. 22,[55][56][57] The crystallinity of as prepared LaPO 4 :Ce,Tb is proven by powder x ray diffraction (PXRD) pattern 55 as well as by high-resolution transmission electron microscopy (HRTEM). Both types of method-as expected-indicate the nanoparticles to crystallize with the monazite type of structure.…”

Preparation of LaPO 4 :Ce 3+ ,Tb 3+ nanophosphors by mixed co-precipitation process and their photoluminescence properties

“…LaPO 4 :Ce 3 þ ,Tb 3 þ phosphors are wellknown for the luminescence characteristics from the 5 D 4 -7 F J transition in the visible range, and have high absorption efficiency under ultraviolet (UV) and vacuum ultraviolet (VUV) excitations. So, LaPO 4 :Ce 3 þ ,Tb 3 þ phosphors have been commercially used as green phosphors in fluorescent lamps, cathode ray tubes, and plasma display panels [3,[17][18][19].…”

Luminescence of nano- and macrosized LaPO4:Ce,Tb excited by synchrotron radiation

“…Since X-ray diffraction data clearly demonstrate the crystallinity of the nanosized sample [17][18][19], we suggest that the nanoparticles surface plays a keyrole with concern to the crystal field perturbation. A significant discrepancy between commercial and nanosized LaPO 4 :Ce,Tb could also seen in the emission spectra of Ce 3+ in Fig 2. Firstly, a characteristic duplet structure of the Ce 3+ emission band in the 300-360 nm range caused by splitting 4f ground level is well resolved in the bulk sample (cf.…”

“…This method as well as peculiarities of LaPO 4 :Ce,Tb nanophosphor were described in detail elsewhere [17][18][19]. A mean particle diameter of 8-10 nm is obtained for the nanopowder.…”