Industrial Waste-Derived Sodalite-Confined Heterojunction: Enhanced Piezo-Photocatalytic Performance for Water Purification

Piezo-photocatalysis that can convert mechanical and solar energy for sustainable wastewater treatment has attracted growing interest. However, its practical piezoelectric response efficiency is often constrained by the rapid recombination of photogenerated electron–hole pairs and catalyst deterioration during the oxidation reaction. Herein, we first propose using sodalite (SOD) to confine heterojunctions to improve their piezoelectric effect and stability. Among a series of sodalite-framed BaTiO3/ZnO configurations synthesized, BaTiO3@sodalite/ZnO (BTO@SOD/ZnO) obtained by in situ growth of sodalite layer on BaTiO3, followed by controlled ZnO deposition, exhibits the most superior piezo-photocatalytic activity and structural stability. Experiments and characterizations revealed that the sodalite confinement significantly enhances the radial piezoelectric response of BTO@SOD/ZnO and promotes efficient electron transfer, enabling efficient and sustainable water purification with minimal metal leaching. The improved piezoelectric potential of BTO@SOD/ZnO was further validated through comprehensive experimental analyses and simulation studies. This work introduces a novel outer-layer confinement strategy to construct well-confined heterojunction interfaces, offering a safe and efficient platform for the development of next-generation piezo-photocatalysts for safer water purification.