Low temperature sintering and color of a new compound Sn_(1.24)Ti_(1.94)O_(3.66)(OH)_(1.50)F_(1.42)

摘要

Nanopowder of a new tin(II) titanium(IV) oxide hydroxide fluoride, Sn_(1.24)Ti_(1.94)O_(3.66)(OH)_(1.50)F_(1.42) with the pyrochlore-type structure (cubic a = 10.3777(7) A, space group Fd-3m) was prepared by using a microwave-assisted solvothermal reaction. The grain size of the nanopowder was 20-30 nm in diameter. Sn_(1.24)Ti_(1.94)O_(3.66)(OH)_(1.50)F_(1.42) decomposed above 300 deg C, but could be sintered to relative density greater than 99 percent by a hydrothermal hot-pressing (HHP) method at 270 deg C and 80 MPa for 4 h. The synthesized powder and solidified body obtained using HHP showed significantly different color, probably due to the difference in water content.