Self-assembled 3D flower-like perovskite PbTiO3 nanostructures and their application in the catalytic oxidation of CO

Abstract

3D flower-like PbTiO₃ nanostructures self-assembled with (101) nanosheets have been realized by the hydrothermal treatment of the mixture of the lead and titanium hydroxides under the effect of high KOH concentration. The layered K₂Ti₆O₁₃ formed in situ under the effect of the high KOH concentration plays an important role in the crystallization of the primary PbTiO₃ nanosheets and the further self-assembly of the 3D flower-like perovskite PbTiO₃ nanostructures. The self-assembled 3D flower-like perovskite PbTiO₃ nanostructures express good mesoporous structures and high specific surface area. In consequence, the 3D flower-like perovskite PbTiO₃ nanostructures as supports show excellent ability to enhance the catalytic activity of Pt. Over the Pt/PbTiO₃ nanoflowers, the CO instantaneously completely converts to CO₂ at a very low temperature of ca. 107 °C facilitating the catalytic purification of the automotive exhaust produced in the cold-start period.