γ-Alumina with hierarchically ordered mesopore/macropore from dual templates

In this paper, we report a procedure using soft/hard dual templates to produce γ-alumina with hierarchically ordered mesopores and macropores (HOMA). Polystyrene spheres colloidal crystals and block co-polymer are sequentially used as templates for ordered macropores and mesopores, respectively. Both macropores and mesopores are ordered pores. The wall of cage-like 500 nm macropores is composed of ordered mesopores of 3.6 nm, and the walls of mesopores are composed of γ-alumina. When loaded with Pt nanoparticles for CO oxidation, Pt/HOMA catalyst shows excellent catalytic properties.