Upconversion emission enhancement of TiO2 coated lanthanide-doped Y2O3 nanoparticles
Lü Qiang(吕强)a)b)†, Zhao Lian-Cheng(赵连城)a), Guo Feng-Yun(国凤云)a), and Li Mei-Cheng(李美成)a)
a Department of Material Physics and Chemistry, School of Material Science and Engineering, Harbin Institute of Technology, Harbin 150001, China; b Center of Electron Microscope Technology, Mudanjiang Medical College, Mudanjiang 157011, China
Abstract To investigate the upconversion emission, this paper synthesizes Tm3+ and Yb3+ codoped Y2O3 nanoparticles, and then coats them with TiO2 shells for different coating times. The spectral results of TiO2 coated nanoparticles indicate that upconversion emission intensities have respectively been enhanced 3.2, 5.4, and 2.2 times for coating times of 30, 60 and 90 min at an excitation power density of 3.21× 102 W$\cdot$cm2, in comparison with the emission intensity of non-coated nanoparticles. Therefore it can be concluded that the intense upconversion emission of Y2O3:Tm3+, Yb3+ nanoparticles can be achieved by coating the particle surfaces with a shell of specific thickness.
Received: 12 November 2007
Revised: 15 November 2008
Accepted manuscript online:
Altmetric calculates a score based on the online attention an article receives. Each coloured thread in the circle represents a different type of online attention. The number in the centre is the Altmetric score. Social media and mainstream news media are the main sources that calculate the score. Reference managers such as Mendeley are also tracked but do not contribute to the score. Older articles often score higher because they have had more time to get noticed. To account for this, Altmetric has included the context data for other articles of a similar age.