Augmenting Antioxidant Enzyme-Like Activity and Hydrogen Evolution of MoS2@Bi2S3 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.