Porous MgTi2O5/MgTiO3 composites with narrow pore-size distribution: in situ processing and pore structure analysis

Abstract

Porous ceramics based on refractory double oxides are promising for the next-generation diesel particulate filter (DPF) materials. Similarly to aluminum titanate (Al2TiO5), MgTi2O5 has a pseudobrookite-type crystal structure with low thermal expansion coefficients among oxides. Since MgTi2O5 has higher stability of pseudobrookite phase than Al2TiO5, it is expected that MgTi2O5-based materials are suitable for the next-generation DPF materials. In this study, porous MgTi2O5/MgTiO3 composites have been prepared by in situ processing (viz. reactive sintering) at 1000–1200°C. Porous MgTi2O5/MgTiO3 composites with very narrow pore-size distribution at the diameter of ∼1 µm were obtained by the pyrolytic reactive sintering at 1000–1100°C. Internal pore-structure was characterized by mercury intrusion–extrusion porosimetry.