Preparation and Performance of 3D-Printed TiO₂-Supported TPMS Structures for Photocatalytic Applications

This study addresses critical bottlenecks in photocatalytic water treatment technologies, including difficulties in recovering traditional powdered catalysts, low mass transfer efficiency in immobilized reactors, and limited structural diversity. By integrating topology optimization with 3D printing technology, we designed and fabricated five types of triply periodic minimal surface photocatalytic reactors (TPMS-PCRs) with hierarchical porous structures-Fischer-Radin-Dunn (FRD), Neovius (N), Diamond (D), I-graph Wrapped Package (IWP) and Gyroid (G). Using fused deposition modeling (FDM), these TPMS configurations were manufactured from polylactic acid (PLA), 1.5 wt% TiO₂/PLA, and 2.5 wt% TiO₂/PLA. The catalytic degradation performance of these structurally distinct reactors for organic pollutants varied significantly. Notably, the FRD-type TPMS-PCR loaded with 2.5 wt% TiO₂ achieved a methylene blue (MB) degradation rate of 93.4% within 2.5 h under rotational flow conditions, compared to 87.5% under horizontal flow conditions.