Augmenting Antioxidant Enzyme‐Like Activity and Hydrogen Evolution of MoS ₂ @Bi ₂ S ₃ Heterojunction via Ultrasound‐Evoked Piezoelectricity for Anti‐Inflammation

Abstract Inorganic piezoelectric biomaterials exhibit significant potential for diverse biomedical applications, yet their limited piezoelectric effect has hindered broader utilization. To address this challenge, the study successfully fabricates a heterojunction MoS ₂ @Bi ₂ S ₃ with exceptional piezoelectric properties through doping engineering. Comprehensive studies reveal that MoS ₂ @Bi ₂ S ₃ efficiently converts mechanical energy into electrical energy, facilitates hydrogen (H ₂ ) evolution, and enhances the antioxidant enzyme‐like performances under ultrasonic irradiation. Moreover, a GSH and GSSG switch cycle is established during the piezocatalytic process, which is conducive to augment the piezoelectricity of MoS ₂ @Bi ₂ S ₃ in biological environment. Further investigations demonstrate that deformation of MoS ₂ @Bi ₂ S ₃ significantly reduced the free energy required for •OH adsorption, thereby dramatically enhancing its •OH scavenging ability. Both experimental and theoretical results verify a narrowed bandgap of MoS ₂ @Bi ₂ S ₃ with or without deformation, indicating that the alteration in bandgap is fundamentally responsible for the enhanced piezoelectric effect, piezocatalytic properties, and H ₂ evolution. Capitalizing on the antioxidant capability of H ₂ and MoS ₂ @Bi ₂ S ₃ itself, the developed MoS ₂ @Bi ₂ S ₃ exhibits anti‐inflammation activity both in vitro and in vivo, suggesting their potential for the treatment of rheumatoid arthritis and other inflammatory diseases.