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We report a facile method to enhance the photoluminescence of 6Y–ZrO 2 : Er3+ translucent ceramics prepared via the vacuum sintering technique by introducing Ag. Ag atoms could be incorporated into the host at high temperatures; these atoms partially precipitated to form Ag nanoparticles during cooling. The intensities of green up-conversion, 1.5 and 2.7 μm emissions under 980 nm excitation, and the green down-conversion luminescence upon 377 nm excitation were improved via co-doping with Ag due to the modification of the local crystal field and the surface plasmon resonance effect. Based on the fluorescence intensity ratio of 2H 11/2 → 4I 15/2 versus 4S 3/2 → 4I 15/2 , 6Y–ZrO 2 : 1 mol%Er3+, 0.67 μmol%Ag exhibited the maximal relative sensing sensitivity of 1.12 %K−1, which could be applied as a potential thermometer with good sensitivity. The present work sheds light on how to simultaneously enhance the emission intensity and thermal sensitivity of Er3+ in ceramics. [ABSTRACT FROM AUTHOR]

A novel fabrication method for reticulated porous ceramics (RPCs) with high strength and high porosity has been proposed based on polymeric replica method and in-situ synthesis of mullite whiskers. Through the FactSage theoretical prediction, the mullite was produced in A10, A15 and A20 coating slurries and the liquid phase viscosity was decreased with increasing sintering temperature and AlF 3 content. The results show that as the AlF 3 content in coating slurry increases, the amount of mullite phase increases and the internal pore structure of the struts in the RPCs changed from triangular to rounded. Adding appropriate AlF 3 content in the coating slurry facilitated the growth of mullite whiskers, but excessive AlF 3 content caused the formation of amorphous crystals. The method used here improved the compressive strength without significantly reducing the porosity. Compared to untreated specimens, the compressive strength and residual strength ratio of sample A15 were increased by 38.24% and 19.75%. [ABSTRACT FROM AUTHOR]