Sol-hydrothermal synthesis and optical properties of Eu3+, Tb3+-codoped one-dimensional strontium germanate full color nano-phosphors

Abstract

Novel near-UV and blue excited Eu(3+), Tb(3+)-codoped one dimensional strontium germanate full-color nano-phosphors have been successfully synthesized by a simple sol-hydrothermal method. The morphologies, internal structures, chemical constitution and optical properties of the resulting samples were characterized using FE-SEM, TEM, HRTEM, EDS, XRD, FTIR, XPS, PL and PLE spectroscopy and luminescence decay curves. The results suggested that the obtained Eu(3+), Tb(3+)-codoped strontium germanate nanowires are single crystal nanowires with a diameter ranging from 10 to 80 nm, average diameter of around 30 nm and the length ranging from tens to hundreds micrometers. The results of PL and PLE spectra indicated that the Eu(3+), Tb(3+)-codoped single crystal strontium germanate nanowires showed an intensive blue, blue-green, green, orange and red or green, orange and red light emission under excitation at 350-380 nm and 485 nm, respectively, which may attributed to the coexistent Eu(3+), Eu(2+) and Tb(3+) ions, and the defects located in the strontium germanate nanowires. A possible mechanism of energy transfer among the host, Eu(3+) and Tb(3+) ions was proposed. White-emission can be realized in a single-phase strontium germanate nanowire host by codoping with Tb(3+) and Eu(3+) ions. The Eu(3+), Tb(3+)-codoped one-dimensional strontium germanate full-color nano-phosphors have superior stability under electron bombardment. Because of their strong PL intensity, good CIE chromaticity and stability, the novel 1D strontium germanate full-color nano-phosphors have potential applications in W-LEDs.

Effects of the Concentration of Eu3+ Ions and Synthesizing Temperature on the Luminescence Properties of Sr2−xEuxZnMoO6 Phosphors

“…Previously, Lin et al successfully synthesized novel near-UV and blue-excited Eu 3+ , Tb 3+ -co-doped one-dimensional strontium germanate full-color nanophosphors by a simple sol-hydrothermal method. They found that incorporation of the Eu 3+ and Tb 3+ ions into strontium germanate resulted in a slight shrinkage of the lattice constants and the unit cell volume because Eu 3+ and Tb 3+ had smaller radii than Sr 2+ , indicating the Eu 3+ and Tb 3+ ions had been incorporated into the host lattice of SrGe 4 O 9 and did not change the crystal structure [24]. Those results also suggested that the Eu 3+ ions substituted into the sites of Sr 2+ ions.…”

“…When the synthesizing temperature was 1200 °C, the emission intensity of the transition of 5 D0-7 F2 (616 nm) for Sr1.9Eu0.1ZnMoO6 and Sr1.88Eu0.12ZnMoO6 phosphors was higher than that of 5 D0-7 F1 (597 nm), as Figure 4 shows. The transitions of 5 D0-7 F1 (588 nm), 5 D0-7 F2 (612 nm), 5 D0-7 F3 (649 nm), and 5 D0-7 F4 (695 nm) for the Eu 3+ ions can be simultaneously observed in the emission spectrum of the Eu 3+ , Tb 3+ -co-doped one-dimensional strontium germinate, full-color nano-phosphors [24]. However, introduction of the Eu 3+ ions in the Sr2−xEuxZnMoO6 lattice results in disorder.…”

“…The disorder in the structure will cause transitions in 5 D0-7 F2 and point defects in the lattice because of differences in the chemical valence and in the ionic radius between Eu 3+ ions and Sr 2+ ions. The Eu 3+ ions could occupy either of the sites , and 5 D 0 -7 F 4 (695 nm) for the Eu 3+ ions can be simultaneously observed in the emission spectrum of the Eu 3+ , Tb 3+ -co-doped one-dimensional strontium germinate, full-color nano-phosphors [24]. However, introduction of the Eu 3+ ions in the Sr 2−x Eu x ZnMoO 6 lattice results in disorder.…”

Growth of Li Doped Bismuth Oxide Nanorods and its Electrochemical Performance for the Determination of L-Cysteine

“…The 0.1 M KCl solution was prepared from potassium chloride and deionized water. Li doped bismuth oxide nanorods were synthesized by the hydrothermal process which was similar to that reported by Lin et al 25 Briefly, sodium bismuthate and lithium acetate with the mass ratio of 21:5 were mixed with 60 mL deionized water at room temperature with magnetic stiring for 0.5 h. Then the mixtures with lithium acetate and sodium bismuthate were transferred into a Teflon-lined stainless autoclave. The stainless autoclave was sealed and heated to 80-180 ºC and maintained for 0.5 h to 24 h. The white precipitates were gained by the centrifugation, washed using deionized water for several times.…”

Ce Doped Germanium Dioxide Nanowires and Solar Light Photocatalytic Performance

“…Hydrothermal route is an effective method for the synthesis of doped one-dimensional (1D) nanoscale materi-als [14][15][16][17]. In the paper, Ce doped germanium dioxide nanowires have been synthesized by the hydrothermal route using germanium dioxide and Ce acetate as the raw materials, sodium dodecyl sulfate (SDS) as the surfactant.…”