Dual-Defect Regulated G-C₃N₄ for Piezoelectric Catalytic Tumor Therapy with Enhanced Efficacy

Piezoelectric catalysis for tumor treatment is an emerging method for generating reactive oxygen species (ROS). However, the development and optimization of piezoelectric catalytic nanomaterials remain the major challenge. Herein, by regulating the internal and surface defects of graphene phase carbon nitride (defect-engineered g-C₃N₄), its piezoelectricity and sonocatalytic performance is enhanced, thus achieving efficient tumor treatment. By reducing bulk defects, the charges excited by ultrasound (US) within the defect-engineered g-C₃N₄ can migrate more rapidly to the material surface, thereby enhancing their participation in redox reactions. Increasing surface defects not only introduce more active sites on the surface of defect-engineered g-C₃N₄ but also enhance the asymmetry of the defect-engineered g-C₃N₄ structure, resulting in excellent piezoelectric properties. This defect-engineered g-C₃N₄ nanosheet can effectively generate ROS in tumor cells and induce tumor cell apoptosis under US stimulation. This work not only introduces a method to enhance the piezoelectric catalytic performance of g-C₃N₄ but also expands the potential application of defect-engineered piezoelectric materials to tumor treatment.