Influence of Bi2S3 on the optical properties of γ-La2S3 ceramics

γ-La2S3 ceramics with Bi2S3 as additives were prepared by hot-pressed sintering. The microstructures and optical properties of these ceramics were studied. When the Bi2S3 content was 0.1 wt.%, the maximum transmittance was increased from 33% to 45%. Further increase in Bi2S3 content decreased the IR transmittance. The existence of Bi phase was the main factor responsible for the difference in transmittance of the pellets with various levels of Bi2S3.

Research highlights
► Bi2S3 was used to be sintering additive of La2S3 ceramics for the first time.
► The IR transmittance was increased from 33% to 45%.
► Bi2S3 could decompose at the sintering temperature.