Quantum dots protected from oxidative attack using alumina shells synthesized by atomic layer deposition

Applications of luminescent quantum dots require the materials to be stable under a wide range of temperatures, photon fluxes and chemical environments. In this work, we demonstrate that Al₂₃ shells synthesized by atomic layer deposition on films of CdTe quantum dots are effective to prevent chemical degradation for up to 17 hours under continuous illumination at 90 °C in ambient air. Control samples with no Al₂₃ coating experienced extensive oxidation and severe quenching of the photoluminescence intensity under these conditions.