High efficiency near infrared emission from Pb1-xSrxSe Quantum dots in lithium aluminosilicate glass-ceramics

Pb _1-xSr _x Se quantum dots (QDs) were prepared in Li ₂O-Al ₂O ₃-SiO ₂ (LAS) glass-ceramics with 0–2.0 mol% SrO by conventional melt-quenching method. The near-infrared photoluminescence and photodarkening properties of Pb _1-xSr _xSe QDs in LAS glass-ceramics were studied. Upon the heat treatments of 490–550 °C for 10 h, there are LiAlO ₂ nanocrystals and PbSe QDs co-existed in the glassy matrix without SrO, and 1024–1745 nm near infrared emission from PbSe QDs were realized. With the increasing of SrO concentration from 0 to 2 mol%, the absorption wavelengths blue-shifted from 1738 to 1380 nm at 540 °C, the PL peak wavelengths blue-shifted from 1788 to 1538 nm at 540 °C. The blue-shifts are attributed to the increasing bandgap by incorporation of Sr ²⁺ ions into PbSe crystalline lattice. Pb _1-xSr _xSe QDs display better photoinduced anti-darkening properties than pure PbSe QDs with the increasing of pumping power, and the Pb _1-xSr _x Se QDs embedded in the LAS glass with 2.0 mol% SrO shows the highest photoluminescence quantum yield of ∼36.9%.