The Preparation And Luminescence Properties Of Barium Titanate Inverse Opal Structure Doped With Ytterbium And Thulium

The progress of science and technology bring convenience for people’s production and life. At the same time, It also bring the inevitable contradiction between man and nature:Human’s growing material needs and natural resource supply; In order to obtain greater benefits, human beings damage the environment, leading to land desertification, air pollution, water shortage, and so on. Whether people can rely on technological progress to solve these problems, is a very good research topic.In the case of limited resources, improving the efficiency of resource utilization is a great choice. Barium titanate has high dielectric constant as an excellent ferroelectric material. Barium titanate has been widespread concerned since it was found. It is used in information storage, holographic camera, voltage switch, pressure sensor, piezoelectric ceramic, etc. The rare earth up-conversion is also called the antistokes emitting, referring to use low frequency light to inspire high frequency light. Putting the rare earth element into the semiconductor material and improduing certain properties is a direction in functional materials research today. The ytterbium and thulium have a good level matching, So it can improve the up-conversion luminescence of thulium when they were codoped together. At the same time, it can also improve the properties of ferroelectric while the thulium and the ytterbium are doped to barium titanate.Photonic crystal refers to be the structure that the dielectric constant changes periodically. It has the character of photonic band gap and photon localization. The photonic band gap can be adjusted through the structure and dielectric constant. And the light can be modulated by the photonic band gap. When the frequency of the light falls within the photonic band gap, the luminous intensity is restrained; The barium titanate which is doped with the thulium and the ytterbium is prepared with the structure of photonic crystal, the light can be modulated by the photonic band gaps of the structures. And the deformation of barium titanate will happen under the action of external electric field for piezoelectric properties, thus making the photonic band gap will be adjusted. Resultly, we can prepare the functional materials that light can be adjusted.Under this theory, we prepared different size of polystyrene microspheres by soap-free emulsion preparation. And using microspheres prepared the three dimensional photonic crystal templates with different band gaps through cooperative self-assembly method. The barium titanate sol which was double doped with the thulium and the ytterbium was prepared by using sol-gel method, the sol was filled into three-dimensional photonic crystals templates by using the spin coating method, thus the barium titanate with inverse opal structure was prepared. The contrast samples wihtout inverse opal structure is prepared through spin coating method on quartz substrates.Polystyrene three-dimensional photonic crystal templates, barium titanate inverse opals templates and contrast samples were measured in the conditions of transmittance, xrd, SEM, luminescence. The polystyrene microspheres have uniform size particle and arrange neatly in face-centered structure. The Three-dimensional photonic crystals have good photonic band gap. The barium titanate with the inverse opal structure has a good phase, and arranged in rules with the air aperture. It also has good photonic band gap.It can be seen clearly that luminescent properties of inverse opal structures were modulated by the photonic band gap compared with contrast samples. The emitting light was obvious inhibited when falling in the band gap. But the emitting light was obviously enhanced when its frequency falling at the edge of the band gap. All of these results prove the feasibility of our theoretical hypothesis.