A methodology for identifying thermographic phosphors suitable for high-temperature gas thermometry: application to Ce3+ and Pr3+ doped oxide hosts

Abstract

A methodology is presented that utilizes configurational coordinate diagrams in combination with energy level diagrams to select new potential thermographic phosphors for high-temperature gas thermometry applications. Oxide hosts doped with trivalent ions were investigated, and based on the analysis Ce3+ doped ortho-phosphates (GdPO4, LuPO4, YPO4) were selected for testing. All three phosphors had high measured quenching temperatures ( $$T_{50} > 800\, K$$ ), partially validating the methodology used. Additionally, the quenching temperature for Ce:GdPO4 of $$T_{50} = 1000\, K$$ was more than $$150\, {\text{K}}$$ larger than previously seen for trivalent ions doped in oxide hosts. The encouraging results demonstrate that this analysis may be applied to aid in finding thermographic phosphors for gas thermometry at combustion relevant temperatures.