Leveraging Mn-doping to modulate band structure and carrier dynamics in BaTiO3 for efficient piezoelectric-chemodynamic cancer therapy

• Mn-doped BaTiO 3 with modulated band structure and carrier dynamics. • Synergistic SDT/CDT achieved via Mn-doping and piezoelectric catalysis. • US accelerates Fenton-like reactions for improved CDT efficacy. Piezoelectric-based sonodynamic therapy (SDT) under ultrasound (US) excitation has garnered increasing attention in cancer treatment. Barium titanate (BTO) is a typical piezoelectric material with the advantage of good biocompatibility. However, the hypoxic microenvironment of tumors limits the reactive oxygen species (ROS) production of piezoelectric materials. In this study, BTO/Mn/PDA/Trop-2 was prepared via hydrothermal and self-layered assembly methods for the treatment of bladder cancer. The BTO generates reactive oxygen species (ROS) through the piezoelectric effect under US irradiation. The bandgap of BTO was reduced by Mn doping, which accelerated electron movement and enhanced the piezoelectric effect of BTO to strengthen SDT. Additionally, Mn exhibited Fenton reaction activity, converting endogenous hydrogen peroxide into hydroxyl radicals, and US enhanced CDT by promoting Mn release. The enhanced SDT and CDT of BTO/Mn/PDA/Trop-2 demonstrate inhibitory effects on bladder cancer both in vitro and in vivo . This work achieved bladder cancer treatment by simultaneously enhancing the SDT and CDT of piezoelectric materials.