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[摘要]：One-dimensional LaOCl: Ln(3+) (Ln(3+) = Eu3+/Sm3+, Tb3+, Tm3+) nanofibers, nanotubes, and quasi-1D microbelts are successfully prepared by a sol-gel/electrospinning process. XRD, FT-IR, SEM, TEM, as well as photoluminescence (PL) and cathodoluminescecne (CL) spectra are used to characterize the resulting samples. Through a heat treatment process at high temperature, the as-prepared samples are well-crystallized with the tetragonal structure of LaOCl. Under ultraviolet radiation and low-voltage electron beam excitation, the LaOCl: Eu3+, LaOCl: Sm3+, LaOCl: Tb3+, and LaOCl: Tm3+ samples give the characteristic transitions of Eu3+ (D-5(0, 1, 2) -> F-7(0, 1, 2, 3, 4)), Sm3+ ((4)G(5/2) -> H-6(5/2,) (7/2,) (9/2)), Tb3+ (D-5(3, 4) -> F-7(2, 3, 4, 5, 6)), and Tm3+ (D-1(2), (1)G(4) -> F-3(4), H-3(6)), respectively. Moreover, there exists simultaneous luminescence of Tb3+, Tm3+, Eu3+, or Sm3+ individually when codoping them in the single-phase LaOCl host (for example, LaOCl: Tb3+, Eu3+/Sm3+ ; LaOCl: Tm3+, Eu3+/Sm3+; LaOCl: Tb3+, Tm3+, Eu3+/Sm3+ systems), which is beneficial to tune the emission colors. Under low-voltage electron beam excitation (1-5 kV), a variety of colors can be efficiently adjusted in a wide triangle region enveloped by three CIE chromaticity coordinate points [LaOCl: Eu3+, (x = 0.6039, y = 0.3796); LaOCl: Tb3+, (x = 0.2452, y = 0.5236); LaOCl: Tm3+, (x = 0.1456, y = 0.0702)] for mono- and co-doped LaOCl: Ln(3+) (Eu3+, Sm3+, Tb3+, Tm3+) samples, making these materials have potential applications in field-emission display devices. |
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