Effects of hydroxy propyl cellulose (HPC) surfactant on fabrication, microstructure and optical properties of Ce3+:Lu3Al5O12 (Ce:LuAG) transparent ceramics

• Nano-grain sized Ce:LuAG powders are synthesized by co-precipitation method.
• HPC exhibits LCST at 41 °C and hydration–dehydration change in aqueous solution.
• The green compact performs a linear thermal shrinkage of 19.7% from RT to 1500 °C.
• Ce:LuAG transparent ceramics with 73.48% optical transmittance are obtained.
• There are no observable micro-pores and secondary phases at grain boundaries.

Nanosized Ce3+ doped Lu3Al5O12 (Ce:LuAG) powder with narrow particle size distribution and high sinterability were successfully synthesized via a modified co-precipitation method using hydroxy propyl cellulose (HPC) as surfactant. It was suggested that a polymer layer was formed by HPC wrapping on the Ce:LuAG precursors instead of free water during precipitation and drying processes owing to its typical property of lower critical solution temperature (LCST), which could reduce the agglomeration among the particles. The green compact shaped by the powders exhibited a superior linear thermal shrinkage (19.7%) from room temperature to 1500 °C and could be subsequently densified into high optical quality Ce:LuAG transparent ceramics at 1750 °C for 10 h under vacuum sintering without any sintering aids. The in-line optical transmittance of the Ce:LuAG ceramic reached 73.48% at the wavelength of 550 nm without observable micro-pores and secondary phases at grain boundaries or within grains.

HPC created micelles wrapping on the precipitate Ce:LuAG precursors during the preparation process by co-precipitation method to reduce the agglomeration among the particles owing to its typical characteristic of LCST, and the green compact could be densified into high optical quality transparent ceramics without any sintering aids.Figure optionsDownload as PowerPoint slide