A 3D printed synergistic aerogel microreactor toward stable and high-efficiency photocatalytic degradation

Photocatalysis offers a credible and prompt approach to solving the growing problems of environmental pollution and energy shortages. However, the practical application of photocatalytic materials still faces the challenge of the efficient catalytic system without secondary recovery. Herein, hollow Fe 2 O 3 microspheres with uniform size (polydispersity index = 0.067) were synthesized using an innovative microgel template–assisted solvothermal method with high yield. Via direct writing three-dimensional printing, the as-prepared Fe 2 O 3 microspheres and graphene oxide were fabricated into an ultralight, stable, and high-performance aerogel microreactor, achieving wastewater treatment without catalyst recovery. Photocatalytic degradation efficiency of rhodamine B achieved 97.8% by the microreactor under simulated sunlight irradiation for 120 min. The rich porous structures and highly interconnected networks of the microreactor provide high specific surface area and increased numbers of multidimensional mass transfer channels, further enabling the catalytic performance and reusability for photocatalytic degradation.