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Synthesis and luminescence properties of nanosheets derived from layered perovskite K2Gd2−xEuxTi3O10and RbLa1-xTbxTa2O7
| Content Provider | Scilit |
|---|---|
| Author | Ogata, C. Ida, S. Matsumoto, Y. |
| Copyright Year | 2009 |
| Description | Journal: Iop Conference Series: Materials Science and Engineering $Eu^{3+}$ and $Tb^{3+}$− doped perovskite nanosheets, Gd_{2−x}Eu_{x}Ti_{3}O_{10}$^{2−}$ and La_{1-x}Tb_{x}Ta_{2}O_{7}$^{−}$, were prepared by the soft chemical exfoliation reaction of $K_{2}Gd_{2−x}Eu_{x}Ti_{3}O_{10}$ and $RbLa_{1-x}Tb_{x}Ta_{2}O_{7}$ with an ethylamine solution. The thicknesses of the nanosheets were 2.4 nm (Gd_{1.4}Eu_{0.6}Ti_{3}O_{10}$^{2−}$) and 1.8 nm (La_{0.7}Tb_{0.3}Ta_{2}O_{7}$^{−}$). This indicates that the starting layered oxides can be exfoliated by acid exchange and treatment with ethylamine. Intense red and green emission were observed in aqueous solution with Gd_{1.4}Eu_{0.6}Ti_{3}O_{10}$^{2−}$− and La_{0.7}Tb_{0.3}Ta_{2}O_{7}$^{−}$ -nanosheets, under UV illumination with energies greater than the corresponding host oxide band gap. This result indicates that photoluminescence of these nanosheets are assigned to energy transfer from the M-O (M: Ti and Ta) network to $Ln^{3+}$ $(Ln^{3+}$: $Eu^{3+}$ and $Tb^{3+}$) in the nanosheets. In addition, the excitation bands of the Gd_{1.4}Eu_{0.6}Ti_{3}O_{10}$^{2−}$-nanosheet were red-shifted with increasing concentration of the nanosheet solution. This means that broad excitation peaks of the Gd_{1.4}Eu_{0.6}Ti_{3}O_{10}$^{2−}$-nanosheet are not assigned to the charge transfer (CT) transition from $O^{2−}$ to $Eu^{3+}$, but the energy transfer from the Ti-O network to $Eu^{3+}$ in the nanosheet. The strong $Eu^{3+}$ emission intensity of Gd_{1.4}Eu_{0.6}Ti_{3}O_{10}$^{2−}$-nanosheet is presumably due to a two step energy transfer cascade from the Ti-O network to $Gd^{3+}$ and then to $Eu^{3+}$. |
| Related Links | http://iopscience.iop.org/article/10.1088/1757-8981/1/1/012004/pdf |
| ISSN | 17578981 |
| e-ISSN | 1757899X |
| DOI | 10.1088/1757-8981/1/1/012004 |
| Journal | Iop Conference Series: Materials Science and Engineering |
| Issue Number | 1 |
| Volume Number | 1 |
| Language | English |
| Publisher | IOP Publishing |
| Publisher Date | 2009-02-01 |
| Access Restriction | Open |
| Subject Keyword | Journal: Iop Conference Series: Materials Science and Engineering Charge Transfer Aqueous Solution Band Gap Energy Transfer |
| Content Type | Text |
| Resource Type | Article |
