Water-Stable and Photoelectrochemically Active CsPbBr3/Polyaniline Composite by a Photocatalytic Polymerization Process

Inorganic perovskite quantum dots (PQDs) have emerged as an unprecedented class of optoelectronic materials due to their notable properties. However, their inherent poor stability has become the main impediment restricting the broad applications of PQDs. Herein, with the aim to enhance the stability of PQDs, we developed a photocatalytic polymerization strategy to encapsulate CsPbBr3 PQDs into a polyaniline (PANI) polymer matrix. The resultant CsPbBr3/PANI composite showed exceptional water stability, with its structure and morphology remaining unchanged even after being immersed in water for 4 weeks. Furthermore, the CsPbBr3/PANI composite could maintain approximately 93% of its original photoluminescence (PL) intensity after 4 weeks, while that of pristine CsPbBr3 was fully quenched along with structure degradation. More impressively, the CsPbBr3/PANI composite exhibited improved charge transport properties due to the electrical conductivity of the PANI protective layer, leading to enhanced photoelectrochemical activity in water. This work provides some insights into the rational design of PQDs with high stability and photoelectric properties for optoelectronic and photocatalytic applications.