LAUSR

Mesoporous and dispersed MnAl-based mixed metal oxide catalysts (MnxAlO) were fabricated via the calcination of layered double hydroxide (LDH) precursors prepared by the coprecipitation method. Their physiochemical properties were characterized and their catalytic activities for ozone decomposition were evaluated. The results indicate that the prepared MnxAlO catalysts have excellent catalytic activity owing to their large specific surface area, abundant surface oxygen vacancies and lower average Mn oxidation states. The Mn/Al atomic ratio and calcination temperature are found to significantly affect the textural properties and catalytic activity for ozone decomposition. The Mn2AlO-400 catalyst (Mn/Al = 2, calcined at 400 °C) exhibited 84.8% ozone conversion after 8 h reaction under an initial ozone concentration of 45 ± 2 ppm, 30 ± 1 °C, a relative humidity of 50% ± 3%, and a space velocity of 550 000 h−1. The results also show that the catalytic activity of Mn2AlO-400, which was deactivated owing to the accumulation of oxygen-related intermediates, was recovered by calcination at 400 °C under a N2 atmosphere for 1 h. A possible reason for catalyst deactivation and regeneration is proposed. This work provides a facile method for fabricating MnxAlO catalysts with excellent characteristics to achieve better catalytic activity, which are promising candidates for practical ozone decomposition.