The electron transfer and the frame trap effect of the anti-virus nano-scheelite
Eu3 +-doped nano-scheelite which has anti-virus activity have been prepared and the size of the nano-particle is about 40-50nm. The XRD, TEM were used to give a description about the particles appearance and crystal structure and the HREM image and image simulation are used to calculate and simulation CaWO4:Eu3+ sample. We find that Eu3+ replace the Ca in inversion centre, the others are hold non-inversion centre departure Ca2+, or exist in the crystal as interstitial atoms. The spectrum of the nano-scheelite was character by fluorescence optical spectrometer. The Eu3+ions Fluorescence spectrum also showed that Eu3+ ions are apt to occupy an inversion center in CaWO4:Eu3+ nanocrystals. We can conclude that Eu3+ ions enter into crystal lattice of CaWO4. In the CaWO4: Eu3+ system, Eu3+ ions mostly take up two atomic sites, which replace part of Ca2+ ions and another is replace part of W6+ ions. The scheelite fluorescence probe was used to analyze the relation between luminescence character and crystal site, and then use the relation to describe the atom site of the nano-scheelite crystal in high resolution image and high resolution simulate image intuitively. The surface state structure and the spectrum analyze result shows that the anti-virus activity was related to the physical nature and we also discussed the electron transfer mechanism and the frame trap effect.
nano-scheelite electron transfer frame trap
曹林 羊富强 赵婕 曹洁馨 冯朝源
北京科技大学材料物理系100083 北京大学医学部 北京理工大学
国际会议
成都
英文
2007-11-19（万方平台首次上网日期，不代表论文的发表时间）