Engineering CsPbBr₃ quantum dots with efficient luminescence and stability by damage-free encapsulation with a-SiC_x:H

Although encapsulation is an effective technique to improve the stability of perovskite quantum dots (PQDs), they are prone to photoluminescence (PL) degradation during encapsulation. Herein, a damage-free plasma-based encapsulation technique in combination with real-time in situ diagnosis is designed for CsPbBr₃ QDs films. The CH₄/SiH₄ plasma has little destructive effects on the CsPbBr₃ QDs. The a-SiC_x:H films prepared with the CH₄/SiH₄ plasma by low-temperature plasma-enhanced chemical vapor deposition protect the CsPbBr₃ QDs from surface damage during encapsulation, so that the intrinsic PL efficiency is maintained. Furthermore, the PL intensity is improved by increasing the carbon concentration in a-SiC_x:H and the CsPbBr₃ QDs films encapsulated by a-SiC_x:H show long term stability under harsh conditions such as prolonged air exposure, UV light illumination for more than 60 days, immersion in water, as well as thermal treatment at 205 ^oC.