Alkaline-earth metal sulfide nanocrystals embedded in oxysulfide glasses

Abstract

As a wide band gap semiconductor, alkaline-earth metal sulfides (AES) with low phonon energy, high laser damage threshold, and high transmittance in infrared, have wide application prospects in bioimaging, spectral conversion, and solid-state lighting. However, AES nanocrystals (NCs) suffer from the weak chemical-stability and low mechanical-stability, and can be easily oxidized in humidity and oxygen. Incorporation of AES NCs into inorganic glass is expected to overcome those inherent limitations. In this work, a new type of oxysulfide glass-ceramics containing CaS, SrS, BaS, SrxBa1−xS, and CaxSr1−xS NCs is developed, and average diameters of these AES NCs are tuned in the range of 3–18 nm. Precipitation of AES NCs not only improves the mechanical properties of glass, but also maintains high transmittance (˃60%) in the spectral range of 1–4.3 µm. Results reported in this work offer a new pathway for developing novel oxysulfide glass-ceramics for multi-functional optical devices.