Preparation and Characterization of Mesostructured γ-Manganese Oxide and Its Application to VOCs Elimination

Mesoporous manganese oxide was prepared by using a straightforward, template-assisted method. The resulting material was crystalline and of uniform pore diameter. The material was characterized by HR-TEM, HR-SEM, XRD, XPS, and EXAF-XANES, and pore size distributions were calculated from nitrogen sorption studies. These materials with very high surface area of 316 m 2 /g have a novel hierarchical structure with spherical particles (<1 μm size), which are composed of γ-manganese oxide nanofibrous aggregates with intraparticle mesoporosity. The materials show an exceptionally high ability to eliminate volatile organic compounds (VOCs) at room temperature and the ability increases with increasing temperature. The results indicate that these materials are very promising for applications to emission control and to indoor air purification, as sorbents and catalysts. The materials show very high performance in room temperature removal of NO x and SO 2 even at low concentrations. The VOCs removal ability was further enhanced after Au deposition by a vacuum-assisted laser ablation (VALA) method. Detailed characterization reveals the role of lattice defects, strong metal−support and adsorbate−adsorbent interactions, along with readily available lattice oxygen for the elimination of VOCs.