کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
1616867 | 1005672 | 2011 | 4 صفحه PDF | دانلود رایگان |

Er3+ doped and Er3+–Yb3+ codoped GdOCl phosphors were prepared by modified solid state reaction. X-ray diffraction, scanning electron microscope, and Raman spectrum of the samples were studied. The result of Raman spectrum shows that the cutoff phonon energy of GdOCl is only 505 cm−1, which is beneficial for upconversion luminescence. Infrared-to-visible upconversion emissions were observed under 980 nm diode laser excitation. It was found that the ratio of green to red upconversion emission intensity varies with concentration of the Er3+ or Yb3+ ion. Laser power and doping concentration dependence of upconversion luminescence were studied to understand the upconversion mechanisms. Excited state absorption and energy-transfer processes are proposed to be the possible mechanisms for the visible emissions.
► Synthesis of Er3+ and Er3+–Yb3+ doped GdOCl powders by solid state reaction.
► The phonon cutoff energy of GdOCl is only 505 cm–1.
► The Er3+ or Yb3+ concentration has significant influence on upconversion spectra.
► The green and red emissions originate from a two-photon upconversion process.
► Upconversion mechanism consists of excited state absorption and energy transfer.
Journal: Journal of Alloys and Compounds - Volume 509, Issue 41, 13 October 2011, Pages 9865–9868