# Defect‐Rich 2D Layered Double Hydroxides Enhance Sonodynamic Antibacterial Therapy

## TL;DR

This study creates defect-rich nanosheets that boost sonodynamic therapy's ability to kill bacteria by generating more reactive oxygen species under ultrasound.

## Contribution

A defect engineering strategy using acid etching to enhance sonosensitizer performance for antibacterial applications.

## Key findings

- DR-ZnCuW-LDH nanosheets show fourfold higher ROS generation under ultrasound compared to pristine ZnCuW-LDH.
- Defects and phase transformation improve electron-hole separation and antibacterial efficacy in vitro and in vivo.
- The acid-etching method enables ambient-condition defect engineering without energy-intensive processing.

## Abstract

Sonodynamic Therapy (SDT) is a non‐invasive therapeutic strategy for combating antibiotic‐resistant infections. However, current sonosensitizers typically show limited reactive oxygen species (ROS) output under ultrasound (US) irradiation. While layered double hydroxides (LDHs) feature tunable architectures and favorable biocompatibility for biomedical applications, their potential in SDT‐driven antibacterial systems remains underexplored. Here, we introduce a defect engineering paradigm based on a facile acid‐etching method to construct defect‐rich 2D DR‐ZnCuW‐LDH nanosheets. This ambient‐condition approach enables flexible defect‐phase engineering without energy‐intensive processing. Through this straightforward treatment, the nanosheets undergo a crystalline‐to‐polycrystalline phase transition, form abundant defects with oxygen vacancies (OVs), and narrow the bandgap (Eg) from 3.29 to 1.80 eV, thereby markedly improving electron‐hole separation. Remarkably, DR‐ZnCuW‐LDH nanosheets exhibit a fourfold increase in ROS generation under US irradiation compared to pristine ZnCuW‐LDH, significantly enhancing its performance as an inorganic sonosensitizer for antibacterial applications. This substantial improvement stems from strategically introduced defects and the phase transformation‐induced electronic structure modification. Both in vitro and in vivo evaluations validate the exceptional antibacterial efficacy of DR‐ZnCuW‐LDH nanosheets under US, establishing a versatile platform for sonodynamic antibacterial applications.

This study develops defect‐rich ultrathin ZnCuW‐LDH nanosheets (DR‐ZnCuW‐LDH) via acid etching. DR‐ZnCuW‐LDH exhibits fourfold enhanced US‐triggered ROS production due to oxygen defects and electronic modulation, demonstrating potent antibacterial efficacy in vitro/vivo. This defect engineering strategy presents an advanced inorganic sonosensitizer platform for SDT applications.