Nd:Y2O3 nanopowders for laser ceramics
|Yurii Kopylov 1, Valery Kravchenko , Anatolii Komarov , Zoya Lebadeva , Vladimir Shemet|
1. Fryazino Institute of radioengineering and electronics Russian Academy of Sciences (FIRE RAS), Vvedenskogo sq., Fryazino 141190, Russian Federation
Y2O3 is a promising material for laser oxide ceramics. The Japan team obtained recently Y2O3:Nd and Y2O3:Yb laser ceramics using chlorides water solutions for preparation of starting oxide nanopowders. We used different salt solutions to obtain the powders, doped with Nd. Mixtures of Y and Nd nitrates, oxalates and carbonates were used. Two ways were applied to adjust the solution pH values to Y hydroxide deposition (around 8): 1) addition of urea to the salt solution with subsequent heating to 80-100oC; 2) addition of ammonium hydroxide solution to the salts’ solution. Grain agglomeration, their forms, sizes and surface area depend critically on the experimental conditions. Grain sizes in the range 10-200 nm and surface areas in the range 10-140 m2/g were obtained. Y2O3 powder were obtained by heating hydroxide precursors in air at temperatures 900-1200oC, and the oxide grain surface area was in the range 50-100m2/g. Plates type grains were formed when carbonates’ solutions were used, whereas nitrates and citrates gave more uniform three dimensional grains. Pellets were prepared from the nanopowders using both uniaxial pressure around 2000 kg/m2 and pouring of water-nanopowder mixture into gypsum moulds. Vacuum sintering of the pellets at 1700-1800oC gave transparent ceramic samples. Results of electron microscopy of the samples, Nd absorption and emission spectra are presented.
Presentation: oral at E-MRS Fall Meeting 2005, Laser Ceramic Symposium, by Yurii Kopylov
See On-line Journal of E-MRS Fall Meeting 2005
Submitted: 2005-05-19 13:55 Revised: 2009-06-07 00:44