The cold isostatic press pretreatment process was adopted to prepare fine rare earth oxysulfide up-conversion phosphors with spherical shape, narrow size distribution and high luminescence efficiency. The upconversion...The cold isostatic press pretreatment process was adopted to prepare fine rare earth oxysulfide up-conversion phosphors with spherical shape, narrow size distribution and high luminescence efficiency. The upconversion optical characteristics and brightness of the blue (Y2O2SYb,Tm), green (Y2O2S: Yb,Er), red (Y2O3Yb,Er) emitter were also investigated, and a novel method was successfully developed for the brightness measurement of upconversion luminescence (UPL). It is shown that a white color can be obtained by the appropriate mixture of these primary blue, green and red emissions components. The Er3+ ions exhibit different upconversion mechanism in Y2O2S and Y2O3 host materials. The rare earth oxysulfide is an efficient upconversion matrix. The UPL brightness of Y2O2S: Yb,Er is 6.5 times higher than that of Y2O3: Yb,Er, and Y2O2S: Yb,Er shows UPL brightness of 1100 cd/m2 under 5.56 W/cm2 power density using a 980 nm laser diode.展开更多
Y2O2S:Eu nano crystallines were prepared by a new ethanol assisted combustion synthesis method using sulfurcontained organic fuel in an ethanol-aqueous solution. The as-prepared nanocrystallines were characterized by...Y2O2S:Eu nano crystallines were prepared by a new ethanol assisted combustion synthesis method using sulfurcontained organic fuel in an ethanol-aqueous solution. The as-prepared nanocrystallines were characterized by X-ray diffraction, transmission electron microscope, photoluminescence spectra and X-ray luminescence spectra. It is shown that the assistant fuel ethanol has the effect of decreasing the water needed, simplifying the experiment procedure by dissolving rare earth nitrate and sulfur-contained organic fuel into an even solution, and prompting the formation of rare earth oxysulfide by igniting firstly during heating that leads to combustion decomposition reaction. Y2O2S : Eu nano crystallines with strong photoluminescence and X-ray luminescence are obtained using thioacetamide as organic fuel. Mixtures of Y2O3 : Eu and Y2O2S : Eu are acquired using thiourea as fuel, and the content of Y2O2S : Eu increases until reaches to about half of the Y2O3 : Eu with the increasing amount of thiourea. Y2O2SO4 : Eu emerges when S/Y = 6 and increases with increasing thiourea amount.展开更多
Monodisperse spherical Gd2O2S:Tb nanoparticles have been prepared using an improved homogeneous precipitation method combined with solid-gas sulfuration technology. The effects of Tb3+-doped concentration on luminesce...Monodisperse spherical Gd2O2S:Tb nanoparticles have been prepared using an improved homogeneous precipitation method combined with solid-gas sulfuration technology. The effects of Tb3+-doped concentration on luminescent intensity and color purity of samples were investigated, and the optimal Tb3+-doped concentration was determined. Under the excitation of X-ray, the obtained sample shows excellent luminescent properties, and its luminescent intensity is increased by about 50% under lower sulfuration temperature compared with that of the Gd2O2S:Tb nanoparticles prepared by complex precipitation method.展开更多
基金Supported by the National Natural Science Foundation of China (Grant No.10374011)
文摘The cold isostatic press pretreatment process was adopted to prepare fine rare earth oxysulfide up-conversion phosphors with spherical shape, narrow size distribution and high luminescence efficiency. The upconversion optical characteristics and brightness of the blue (Y2O2SYb,Tm), green (Y2O2S: Yb,Er), red (Y2O3Yb,Er) emitter were also investigated, and a novel method was successfully developed for the brightness measurement of upconversion luminescence (UPL). It is shown that a white color can be obtained by the appropriate mixture of these primary blue, green and red emissions components. The Er3+ ions exhibit different upconversion mechanism in Y2O2S and Y2O3 host materials. The rare earth oxysulfide is an efficient upconversion matrix. The UPL brightness of Y2O2S: Yb,Er is 6.5 times higher than that of Y2O3: Yb,Er, and Y2O2S: Yb,Er shows UPL brightness of 1100 cd/m2 under 5.56 W/cm2 power density using a 980 nm laser diode.
文摘Y2O2S:Eu nano crystallines were prepared by a new ethanol assisted combustion synthesis method using sulfurcontained organic fuel in an ethanol-aqueous solution. The as-prepared nanocrystallines were characterized by X-ray diffraction, transmission electron microscope, photoluminescence spectra and X-ray luminescence spectra. It is shown that the assistant fuel ethanol has the effect of decreasing the water needed, simplifying the experiment procedure by dissolving rare earth nitrate and sulfur-contained organic fuel into an even solution, and prompting the formation of rare earth oxysulfide by igniting firstly during heating that leads to combustion decomposition reaction. Y2O2S : Eu nano crystallines with strong photoluminescence and X-ray luminescence are obtained using thioacetamide as organic fuel. Mixtures of Y2O3 : Eu and Y2O2S : Eu are acquired using thiourea as fuel, and the content of Y2O2S : Eu increases until reaches to about half of the Y2O3 : Eu with the increasing amount of thiourea. Y2O2SO4 : Eu emerges when S/Y = 6 and increases with increasing thiourea amount.
基金Supported by the National Natural Science Foundation of China (Grant No. 10374011)
文摘Monodisperse spherical Gd2O2S:Tb nanoparticles have been prepared using an improved homogeneous precipitation method combined with solid-gas sulfuration technology. The effects of Tb3+-doped concentration on luminescent intensity and color purity of samples were investigated, and the optimal Tb3+-doped concentration was determined. Under the excitation of X-ray, the obtained sample shows excellent luminescent properties, and its luminescent intensity is increased by about 50% under lower sulfuration temperature compared with that of the Gd2O2S:Tb nanoparticles prepared by complex precipitation method.