Multimodal energy harvesting utilizing BiOI nanoflowers with superior adsorption capabilities for efficient piezo-photocatalytic wastewater treatment

Piezo-photocatalysis is a multimodal catalytic process harnesses both solar and mechanical energy for carrier separation and migration. At present, this technology has not been studied much on BiOI materials. Effective coupling of light and mechanical energy with BiOI materials to achieve high piezo-photocatalytic efficiency and reduce secondary pollution of water by catalysts remains a challenge. In this work, BiOI nanoflowers synthesized via solvothermal method, provide a remarkable surface area and exhibit photocatalysis, piezocatalysis and piezo-photocatalysis properties. The BiOI nanoflowers have good piezo-photocatalytic degradation efficiency for organic pollutants, with the highest first-order kinetic coefficient of 0.4549 min⁻¹. Furthermore, a composite porous foam catalyst was developed for enhanced environmental protection and recycling. The nanocomposite not only guarantees a specific catalytic degradation efficiency but also significantly enhances catalyst recovery and prevents secondary water pollution. This study provides a new reference and impetus for future research on piezo-photocatalysis, and also offers a viable and environmentally friendly approach for wastewater treatment through multi-mode energy harvesting.