High-entropy antibacterial materials

High-entropy materials (HEMs), composed of 5 or more principal elements in near-equimolar ratios, have emerged as robust, multifunctional platforms for antimicrobial applications. This review introduces the fundamental principles and structural features of HEMs, focusing on their entropy-driven stability and synergistic properties. Four principal antibacterial mechanisms are discussed: controlled-release of biocidal metal ions, efficient photothermal sterilization, catalytic or oxide-mediated generation of reactive oxygen species, and electrostatic interactions resulting in contact killing. Representative studies illustrate how composition and microstructure can be engineered to optimize antimicrobial efficacy without sacrificing material integrity. The review then summarizes recent progress in applying high-entropy antibacterial materials across diverse areas, including biomedical implants and nanozymes for infection control and cancer therapy, self-disinfecting surfaces for public health, advanced catalysts for wastewater treatment, and antifouling, anticorrosion coatings for marine environments. Finally, current challenges, such as the complexity of compositional design and the need for comprehensive biosafety and environmental impact evaluation, are highlighted, alongside future directions involving computational design, multidisciplinary characterization, and scalable manufacturing. High-entropy antibacterial materials, thus, present a transformative strategy for addressing pathogenic threats, offering durable and broad-spectrum protection in a wide range of applications.