Biodegradable, Biologically Safe Nanogenerators for Self‐Powered Bio‐Integrated Systems

Biodegradable nanogenerators offer a promising route toward self‐powered bio‐integrated systems by converting biomechanical energy into electrical signals while safely degrading after use. Among them, triboelectric and piezoelectric nanogenerators (TENGs and PENGs) are particularly attractive for harvesting low‐frequency physiological motions through soft, flexible, and bioresorbable material systems. This review summarizes recent advances in biodegradable TENGs, PENGs, and hybrid TENG/PENG systems, with a focus on energy‐conversion mechanisms, material selection, device architectures, and integration strategies for wearable and implantable biomedical applications. We further discuss key challenges in performance stability, degradation behavior, biological safety, and system‐level integration, and provide perspectives toward fully transient, self‐powered biomedical platforms.