Transition metal doped cryptomelane-type manganese oxide catalysts for ozone decomposition

By Jinzhu Ma, Caixia Wang, Hong He. 2017

290 citations recorded by the source corpus.

Abstract Transition metal (Cerium, Cobalt, and Iron) doped cryptomelane-type manganese oxide (M-OMS-2) catalysts have been successfully synthesized and characterized. The different metal-ion-doped K-OMS-2 catalysts showed distinct differences in their ozone decomposition activity. Cerium-doped OMS-2 materials showed ozone conversion of 90% under RH = 90% and space velocity of 600,000 h−1. X-ray diffraction (XRD), thermogravimetric analysis (TGA), and X-ray photoelectron spectroscopy (XPS) data suggested that the as-synthesized M-OMS-2 materials were all crystalline with no segregated metal oxide impurities. ICP-OES and XAFS results confirmed that Co3+ and Fe3+ replace Mn3+ in the cryptomelane structure and Ce4+mainly replaces the K+ in the tunnel and partially replaces the Mn4+ in the framework of the cryptomelane structure. Because of the differences in the substitution sites and the ionic radius of dopants, the morphologies of the catalysts were different. The Mn3+content and number of surface defects play a key role during the decomposition of ozone. Ce-OMS-2 is a promising catalyst for purifying waste gases containing ozone under high-humidity conditions.

Subfields: Electrical and Electronic Engineering, Materials Chemistry

View Paper: https://www.semanticscholar.org/paper/c57b15ad104809b596642156ac652ce68af565a4