Nanocrystalline LaOCl:Tb^3+/Sm^3+ as promising phosphors for full-color field-emission displays

Nanocrystalline LaOCl:Tb(3+)/Sm(3+) phosphors were synthesized by a Pechini-type sol-gel process. Under UV and electron-beam excitation, LaOCl:Tb(3+)/Sm(3+) show the characteristic emission of Tb(3+) ((5)D(3,4)-->(7)F(6),...2) and Sm(3+) ((4)G(5/2)-->(6)H(5/2,7/2,9/2)), respectively. In particular, the cathodoluminescence (CL) color of LaOCl:Tb(3+) can be tuned from blue to green by changing Tb(3+)-doped concentration, and their CL intensities (brightness) are higher than those of commercial products Y(2)SiO(5):Ce(3+) and ZnO:Zn, respectively. White CL can be realized by codoping with Tb(3+) and Sm(3+) in a single-phase LaOCl host. The obtained white light is very close to the standard white light. These phosphors are promising for application in field-emission displays.