Yb3+, Er3+ and Tm3+ doped α-Sialon as upconversion phosphor

α-Sialon ceramics are mostly known for high-temperature and high-endurance applications due to their ability to withstand high structural load and their excellent chemical and thermal stability. Here we demonstrate functional α-Sialon ceramics with photon upconversion properties. Intense visible and near-infrared upconversion photoluminescence is observed in Yb3+, Er3+, and Tm3+ doped α-Sialon ceramics prepared by hot press sintering. Clear evidence of α-Sialon formation with the incorporation of Yb3+, Er3+ and Tm3+ ions in the lattice has been established. Emission bands at 498 nm, 551 nm, 662 nm and 802 nm are observed as a result of the two-photon absorption process. The decay behavior of the emission bands suggests the existence of efficient energy transfer from Yb3+ to Er3+ and Tm3+ ions. The possibility of temperature sensing properties has been investigated via high-power laser excitation. These findings could possibly extend the usefulness of Yb3+, Er3+ and Tm3+ doped α-Sialon as an upconversion phosphor material.