Preparation of 3D micro/nanostructured CeO2: Influence of organic/inorganic acids
Runnong Yanga, Lin Yua,*, Ming Suna, Xiangyun Zhaob, Gao Chenga, Wenjin Yea
CeO2 is an important porous material with a wide range of applications in the abatement of volatile organic compounds (VOCs). In this paper, we prepared a series of novel three-dimensional (3D) micro/nanostructured CeO2 materials via a solvothermal method. Organic acid-assisted synthesis and inorganic acid post-treatment were used to adjust the CeO2 microstructures. The size of the 3D micro/nanostructures could be controlled in the range from 180 nm to 1.5 μm and the surface morphology changed from rough to smooth with the use of different organic acids. The CeO2 synthesized with acetic acid featured a hierarchical porosity and showed good performance for toluene catalytic combustion: a T50 of 187 °C and a T90 of 195 °C. Moreover, the crystallite size, textural properties, and surface chemical states could be tuned by inorganic acid modification. After treatment with HNO3, the modified CeO2 materials exhibited improved catalytic activity, with a T50 of ∼175 °C and a T90 of ∼187 °C. We concluded that the toluene combustion activity is related to the porosity and the amount of surface active oxygen of the CeO2. Both these features can be tuned by the co-work of organic and inorganic acids.
3D micro/nanostructure; CeO2; Organic acid; Inorganic acid; Toluene catalytic combustion