Highly stable CsPbBr3 perovskite quantum dots incorporated in aluminum stearate

Abstract

CsPbBr3 perovskite quantum dots (PQDs) have drawn much attention for their high photoluminescence quantum yield and great potential in optoelectronic applications. However, they suffer from poor stability under humid condition. This paper reports CsPbBr3 PQDs incorporated in aluminum stearate (AlSt3) matrix via an improved co-precipitation approach, in which AlSt3 not only acted as hydrophobic matrix to protect CsPbBr3 PQDs from surrounding environment, but also passivated the surface of PQDs via the coordination bond of St-Cs and St-Pb, as well as bond between Al3+ and Br−. By this method, the as-synthesized CsPbBr3-AlSt3 composites exhibited excellent stability in ambient condition even directly in water for more than 60 days. With the CsPbBr3-AlSt3 composites (green emission) used as color-conversion layer, a white light-emitting diode (WLED) was fabricated with a high color rendering index (Ra) of 90 and a low color temperature (Tc) of 4929 K. These results suggest that this method pave an effective way to stabilize CsPbBr3 PQDs, which is of great importance for their further application.