Morphology-controlled synthesis of 3D, mesoporous, rosette-like CeCoOx catalysts by pyrolysis of Ce[Co(CN)6] and application for the catalytic combustion of toluene

Abstract

We synthesized one-dimensional (1D) nanoparticles, 2D hexagonal nanosheets and 3D rosettes of Ce[Co(CN)₆] by a hydrothermal process at different temperatures, and CeCoOx catalysts with similar shapes were obtained by the pyrolysis of Ce[Co(CN)₆]. T₉₀ of 1D nanoparticles, 2D hexagonal nanosheets and 3D rosette-like CeCoOx catalysts was 306, 275 and 168 °C, respectively. The 3D ordered mesoporous rosettes of CeCoOx had superior catalytic activity for toluene combustion, superior thermal stability and moisture resistance, and curves for three consecutive catalytic runs showed overlapping due to more oxygen vacancies, larger pore sizes, more surface Ce³⁺ species, more surface Co³⁺ species, and chemically adsorbed oxygen on the surface.