High-Efficiency Photocatalytic Reactors Fabricated via Rapid DLP 3D Printing: Enhanced Dye Photodegradation with Optimized TiO<sub>2</sub> Loading and Structural Design
Chien‐Hua Chen, Shicheng Wang, Hua‐Wei Chen, Ting-Yi Chou, Chieh-Sheng Chang
Abstract
The photocatalytic degradation of organic compounds is seen as a pivotal water treatment technology. While 3D printing has been proven to directly produce photocatalytic reactors, research in this area, especially utilizing mass-production-capable vat photopolymerization (VP)-based 3D printing, remains in its early stages. This study aimed to prepare high-solid content printing slurries (up to 50 wt %) using the common TiO 2 nanoparticle (P25) photocatalyst to rapidly print reactors with high photodegradation efficiency. The 3D-printed photocatalytic reactors, made by using the prepared slurry, successfully demonstrated complete 100% photodegradation of common organic synthetic dyes (methylene blue, safranin O, and brilliant green). Moreover, photocatalytic reactors with triply periodic minimal surface (TPMS) structures were successfully printed. The reactors with a Diamond structural (D-type) design showed a reaction rate constant of 0.0127 min –1, which is 2.4 times higher than that of the Fischer-Koch S structural (F-type) reactors at 0.005 min –1, underscoring the significant impact of reactor structural design on photodegradation efficiency. Finally, the study showcased the potential for direct manufacturing through the batch production of photocatalytic reactors via whole build-plate 3D printing. Achieving high-speed fabrication, the process was completed within 120 min on a 19.2 cm by 10.8 cm build platform, accommodating the batch printing of 10 photocatalytic reactors, each 1.3 cm in diameter and 2 cm in height.