| Nanostructured materials are expected to play a crucial role in the future technological advance in electronics, optoelectronics, and memory devices. One-dimensional nanostructures in particular offer fundamental opportunities for investigating the effect of size and dimensionality on their collective optical, magnetic, and electronic properties. Therefore, over the past few years, attention has been focused on the research field of nanometer-scale materials. And, the study of self- or induced-assembly of nanostructure and the photophysical properties has been the focus of the nanoscience. Rare earth plays an important role in luminescence, magnetics and superconductor, so rare-earths doped luminescence materials have attracted great attention since their extensive applications in the fields such as information display, advanced laser materials and fiber optical communication and other functional materials.In 1994, R. N. Bhargava et al. reported that ZnS:Mn nanocrystals (NCs) were of much higher extertal luminescent quantum efficiency (QE) than the bulk ones. Although this conclusion was seriously criticized later, the studies on luminescent properties of doped NCs are attracting great interest now, because it is significant not only for potential applications but also for essential understanding of NCs. And the earlier research about rare-earth doped nanocrystallites can be found in B. M. Tissue and his co-workers.Since the discovery of carbon nanotubes in 1991, by Iijima, which was formed from graphite with arc discharge. Attention world wide is focused on nanosized materials of different shapes, as film, wire, rodlike, and tubular forms, due to their importance in studying physical and chemical properties of molecules confined in these nanofabrications and their potential application in fields such as optics, electronics, magnetics, advance catalysis and energy storage/conversion. The possibilities of chemically and physically modifying the outer and inner surfaces and edges also enhanced the advantageous characteristics of nanotubular materials.Among these rare-earth-containing materials, recently, Eu3+-doped fluorescent materials are currently generating much interest for the application as lighting, CRT, PDP and FED devices.In the case of Eu3+ ion, as the energy gap of 5D0—7FJ (J=0-6) is much larger than that of 5DJ+1—5DJ (J=0-3), therefore, the multiphonon relaxation process is predominant between the 5DJ levels and radiative emission mainly occurs from the 5D0 level to 7FJ (J=0-6) in oxide hosts with higher phonon energy. It was found that, the transition of 5D0—7FJ (J=0-6) are sensitive to the local structure around Eu3+ ion. Thus, the Eu3+ ion is a good probe.Here, we used self-or induced-assembly of sodium dedocylsulsate process to prepare Lu2O3:Eu3+ nanocrystallites and Y2O3:Eu3+ nanotubes. Transmission electron microscopy (TEM) images of Lu2O3:Eu3+ nanocrystallines at different temperatures show, the average crystal sizes are 40~50nm (at 450℃), 30~40nm (at 550℃), 10~30nm (at 750℃), respectively. X-ray diffraction (XRD) indicated the crystal phases of calcined powders of Lu2O3:Eu3+ nano-crystallites is cubic phase. A significant increase in the overall intensity and a change in spectral nature of these bands are observed in Lu2O3:Eu3+ nano-crystallites with an increasing temperature . Here , the emission peaks associated to 5D0→7F2 transition under 235nm excitation and the excitation peaks (monitored at 612nm) occurred red shift upon increasing the calcined temperature, the red shift wavelengths valued from 608nm to 615nm in emission spectra and from 235nm to 279nm in excitation spectra, respectively.In the case of Y2O3:Eu nanotubes.TEM image confirms the formation of Y2O3:Eu nanotubes. The typical outer diameters of the nanotubes are in the range of 20–30 nm and the walls are estimated to be several nanometers in thickness.Under 394 nm excitation, two emission peaks are observed at 610nm and 618nm, respectively. The peak at 610 nm is due to the forced electric dipo...
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