Perovskite quantum dots: pioneering nanoplatforms for light-driven pathogen control and environmental purification.

Perovskite quantum dots (PQDs) have emerged as versatile nanomaterials with exceptional optoelectronic and photocatalytic properties, offering great potential for environmental remediation and antimicrobial defense. This review provides the comprehensive overview of PQDs as multifunctional platforms capable of both pollutant degradation and light-driven bacterial inactivation, achieving > 99% bacterial inactivation under visible light. It systematically summarizes recent advances in synthesis methods, surface modifications, and mechanistic pathways related to reactive oxygen species (ROS) generation, charge transfer dynamics, and microbe-surface interactions. Both lead-based and lead-free PQDs are discussed, with emphasis on enhancing their stability, biocompatibility, and environmental safety through surface engineering and green synthesis approaches, such as silica encapsulation yielding 85% fluorescence retention after 90 days in water. Furthermore, the review highlights practical implementations in water purification, food safety, and sustainable disinfection technologies, while also addressing biomedical extensions such as wound treatment. Finally, the major challenges-including aqueous instability, potential toxicity, and scalability-are outlined, along with future perspectives for designing eco-friendly, durable, and efficient PQD-based systems. Overall, this work establishes a foundation for advancing PQDs as next-generation nanomaterials for sustainable antimicrobial and photocatalytic applications.