镱浓度对钬镱双掺二氧化钛上转换发光的影响

以钛酸丁酯为前躯体,乙醇为溶剂,冰乙酸为催化剂,用溶胶-凝胶法制备了TiO2∶Ho3+/Yb3+上转换发光纳米粉体,并研究其上转换发光机制.通过X射线衍射,能谱及扫描电镜对样品进行表征,结果表明样品是金红石型结构的粉体,样品中含有所掺杂的元素Ho和Yb,样品颗粒非常细小,直径约为100 nm,呈球形,并有明显的团聚现象.在常温下选用中心波长为980 nm、最大输出功率500 mV二极管激光器作激发光源测定样品的上转换发光性能,结果显示:在TiO2∶Ho3+/Yb3+样品的上转换荧光光谱中观察到红光和绿光,且绿光的强度比红光的强,绿光的强度约是红光强度的两倍,当Yb3+离子浓度为2.5 mol%时,位于543 nm处绿光的发射强度达到最大值.并详细研究了上转换发光机制.

Effect of the Yb3+Concentration in Upconverting of Ho3+/Yb3+ Co-doped TiO2

The Ho3+/Yb3+co-doped TiO2 sol was prepared through Sol-Gel method,Ti(OC4H9)4 was chosen as a precursor,and ethanol as impregnant,acid as catalyzer,and its upxonverted luminescence mechanism was studyed.By means of X-ray diffraction,energy spectrum and scanning electron microscope samples characterization,and the results show that the structure of the sample is rutile,samples contained by powder doped Yb,sample Ho and element of very small particles diameter is about 100 nanometers,spherical shape,and has obvious reunion phenomenon.At room temperature for 980 nm wavelength selection center,maximum output power for the diode laser 500 mV do stimulate light stimulates samples.In TiO2∶Ho3+ / Yb3+ sample find red and green,the emission strength of red is two times of green.When the doping concentration of Yb3+ is 2.5 mol%,fluorescence spectroscopy 543 nm conversion in observed strong green emission.The mechanisms of the upconversion luminescence were researched.