Schottky engineering of GDYO@Pt to boost piezoelectric and oxidative stress modulation for accelerated cranial regeneration.

Abstract

Piezoelectric stimulation regulates cellular metabolism and enhances bone repair. However, the overproduction of reactive oxygen species (ROS) and hypoxia-induced oxidative stress reduce the efficacy of electrical stimulation and hinder regeneration. Here, a platinum-decorated graphdiyne oxide (GDYO@Pt) multifunctional piezoelectric semiconductor was engineered to eliminate ROS and oxygen self-supply while enabling electrical stimulation. In this system, the interface dipole drives a built-in electric field, triggering charge redistribution in GDYO and breaking symmetry to amplify piezoelectricity. Ultrasound-triggered polarized charges at the Schottky junction lower the barrier and promote GDYO→Pt electron transfer for hydrogen production, where the generated H₂ neutralizes cytotoxic •OH radicals, while the holes/nanozyme drive H₂O₂ → O₂ conversion, synergistically alleviating oxidative stress. In vitro and vivo studies demonstrate that ultrasound-activated GDYO@Pt accelerates cranial defect repair via osteogenesis, angiogenesis, and immunomodulation. This work shows piezoelectric-catalytic synergistic bone regeneration, where the GDYO@Pt heterointerface integrates energy conversion with biological regulation through an engineered asymmetric structure.