Customizable 3D-Printed SiC Photocatalysts for Microplastic Capture and Degradation under Flow and Static Conditions

Abstract

The persistence of microplastics (MPs) in aquatic systems endangers both ecosystems and human health. Among emerging strategies, photocatalytic degradation using semiconductors is a promising approach to MP remediation. Yet, conventional systems employing photocatalystict slurries suffer from poor recoverability, limited reusability, and scalability issues. Herein, a 3D-printed silicon carbide (3D-SiC) photocatalytic platform with tailored architectures and interconnected porous networks is presented for the simultaneous capture and degradation of MPs in both static and continuous flow conditions. The interconnected porous design enhances light absorption and interaction with the MPs, while the robust SiC framework ensures reusability and mechanical integrity. Using polystyrene (PS) microparticles as a model system, the 3D-SiC demonstrates remarkable photocatalytic performance, achieving 85% MPs removal in just 8 h, and a 4.2-fold increase in the carbonyl index (CI) after 60 h of simulated sunlight irradiation. Remarkably, the 3D-SiC retained high photocatalytic activity under dynamic flow conditions, a critical criterion for potential application in water treatment systems. Its mechanical durability, structural adaptability, and consistent reusability over multiple operational cycles further reinforce its suitability for real-world deployment. This work introduces a customizable and reusable photocatalytic platform, representing a significant step toward the practical application of 3D-printed functional materials in MPs remediation.