Perovskite-based photocatalysis for microbial inactivation: materials, mechanisms, and challenges

Perovskite nanomaterials have emerged as next-generation photocatalysts for antimicrobial applications due to their exceptional optoelectronic properties, tunable band gaps, and efficient generation of reactive oxygen species (ROS). These features enable visible light-driven microbial inactivation, presenting a promising alternative to conventional, UV-activated photocatalysts. This review offers a comprehensive and interdisciplinary perspective on the structural and compositional diversity of perovskites, encompassing hybrid organic-inorganic, inorganic, layered, and double perovskite systems, as well as their relevance to photoactivated antimicrobial action. Furthermore, we elucidate the mechanisms by which ROS generated by photoexcited perovskites interact with key cellular components, resulting in oxidative stress, membrane disruption, and bacterial cell death. The review highlights strategies to enhance photocatalytic performance, including elemental doping, heterojunction formation, surface passivation, and encapsulation, which optimize charge separation, improve material stability, and minimize toxicity. Additionally, we summarize the efforts made for the real-world deployment of these systems and the factors that need to be optimized and modulated, including the design of photocatalytic systems in the form of suspended or immobilized systems, as well as advanced photoreactor configurations tailored for water disinfection and surface sterilization. We also present a comparative evaluation of perovskite-based photocatalysts with traditional alternatives, demonstrating their superior visible-light responsiveness and ROS generation efficiency. Applications in healthcare, water purification, and smart textiles are discussed, alongside challenges such as lead toxicity, long-term photostability, and environmental safety. This review presents an integrated framework for understanding and advancing perovskite-based photocatalysts, laying the groundwork for translational research and sustainable antimicrobial technologies in diverse settings.