Catalytic oxidation of toluene by SrTi1-XBXO3 (B = Cu and Mn) with dendritic morphology synthesized by one pot hydrothermal route

Abstract

This work is focus in the effect of B-site cations of SrTiO3 perovskites with non-common morphology (dendritic) on the catalytic behavior of the toluene oxidation reaction. SrTiO3 perovskites doped by two different transition metals (Cu or Mn) were synthesized by the one pot hydrothermal method and characterized by several techniques. The perovskite structure and the dendritic morphology were confirmed by XRD and SEM analyses for all catalysts. In addition, similar textural properties were observed among the catalysts. The addition of metal-dopants provides good stability during three catalytic cycles and in the lifetime test. However, segregation of Cu as CuO was observed on the surface of the Cu-doped catalyst. In contrast, the addition of Mn resulted in the incorporation of Mn4+ in Ti4+ sites present into the structure of the perovskite. This incorporation also enhances the relation Oads/Olatt and the catalytic properties. Finally, the catalyst doped by Mn presented the highest catalytic activity with complete conversion of toluene to CO2 at temperatures below 350 °C.