Room-temperature catalytic removal of low-concentration NO over mesoporous Fe-Mn binary oxide synthesized using a template-free approach

A novel template-free approach, the controlled thermal decomposition of single-phase Fe-Mn binary oxalate, was proposed and used to synthesize mesoporous Fe-Mn binary oxide, which possessed homogeneous worm-like mesopores (4-5nm) and high surface areas above 200m²/g. The catalyst was efficient in the catalytic removal of low-concentration NO at room temperature: 100% removal of 10ppm NO in the first 4h at a high space velocity of 40,000h^-1 on a Fe-Mn binary oxide with a Fe/Mn ratio of 1/4 calcined at 300°C. Catalysts with other Fe/Mn ratios or calcined at higher temperatures showed lower NO removal performances. A synergetic effect between Mnⁿ⁺ and Feⁿ⁺ was proposed and believed to be responsible for the catalytic conversion of NO and O₂ into NO₂, which was subsequently adsorbed and/or absorbed as nitrates on the binary oxide.