Fabrication of Macroporous TiO₂ Loaded with Magnetite for Photocatalytic Degradation of Methylene Blue

Abstract

A macroporous TiO₂ photocatalyst loaded with fine magnetite particles was prepared by the PMMA-templating method for the degradation of methylene blue. The photocatalyst particles synthesized in this study were porous and had uniform macropores. The size of macropores on the photocatalyst was easily controlled by selecting a proper size of PMMA microspheres used as a template. The size of PMMA spheres commercially available were 0.15–1.5 µm, finally leading to porous products with the pore size of 0.14–1.0 µm, which gave rise to high BET surface areas of 14–58 m²/g. In the photocatalytic degradation of methylene blue, the highest activity was exhibited with the porous TiO₂ possessing the smallest pores and highest surface area among the various-sized photocatalysts. The high surface area attributing to the controlled porous structure effectively contributed to an improvement of the degradation performance.