摘要(英) |
Spectroscopy techniques such as photoluminescence (PL), excitation, and time-resolved spectra were used to investigate the coordination polymers, YxSm2-x(C8H10O4)3, synthesized by mid-temperature hydrothermal method. The coordination center is either Yttrium (Y) or Samarium (Sm), and the ligand is1,4-cyclohexanedicarboxylate (C8H10O4, CHDC). Single and powder X-ray diffraction data confirm the structure and purity of these compounds. Inductively-coupled plasma atomic emission spectroscopy (ICP-AES) verifies the elemental compositions of coordination centers. Previous study found a variation in the Sm3+ decay curves in these compounds at different excitation wavelengths as well as different concentrations. In this thesis, the excitation wavelength of exciting Sm3+ to its lowest upper state is adopted to record new emission spectra and decay curves with more higher Sm3+ concentration samples. The analysis of these data exhibits that Sm3+ emission decay curves show a two-stage emission behavior, and the concentration-dependent quenching is observed in both stages. Quenching mechanisms are proposed for explaining the emission quenching behaviors in these compounds. |
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