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

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 MoS₂@Bi₂S₃ with exceptional piezoelectric properties through doping engineering. Comprehensive studies reveal that MoS₂@Bi₂S₃ efficiently converts mechanical energy into electrical energy, facilitates hydrogen (H₂) 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 MoS₂@Bi₂S₃ in biological environment. Further investigations demonstrate that deformation of MoS₂@Bi₂S₃ 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 MoS₂@Bi₂S₃ with or without deformation, indicating that the alteration in bandgap is fundamentally responsible for the enhanced piezoelectric effect, piezocatalytic properties, and H₂ evolution. Capitalizing on the antioxidant capability of H₂ and MoS₂@Bi₂S₃ itself, the developed MoS₂@Bi₂S₃ exhibits anti-inflammation activity both in vitro and in vivo, suggesting their potential for the treatment of rheumatoid arthritis and other inflammatory diseases.