Probing High Oxygen Activity in YSZ Electrolyte

The redox behavior of terbium and praseodymium doped yttria-stabilized zirconia (YSZ) is studied. aim to identify spectroscopic probes a suitable experimental procedure monitor the oxygen activity in YSZ electrolytes solid oxide cells with spatial resolution at operation conditions (e.g. high temperatures). Sintered ceramics crystals 0.3 10 at% content Pr or Tb ions were prepared. Upon equilibration atmospheres from ?20 100 bar P O 2 around 800 °C, majority these rare earth are 3 + oxidation state. At pressures above 0.001 bar, small proportion 4+ formed give rise intense optical absorption 300–500 nm decreased reflectance. From reflectance measurements it shown that concentration increases as 1/4 , correspond trapping holes generated upon incorporation . This competitive causes decrease 3+ luminescence. A quantitative relationship luminescence intensity °C has been found, which compatible model. could be very roughly estimated order ? m.