Partic. vol. 37 pp. 17-25 (April 2018)
doi: 10.1016/j.partic.2017.07.001

Preparation of 3D micro/nanostructured CeO₂: Influence of organic/inorganic acids

Runnong Yang^a, Lin Yu^a,*, Ming Sun^a, Xiangyun Zhao^b, Gao Cheng^a, Wenjin Ye^a

gych@gdut.edu.cn

Abstract

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.

Graphical abstract

Keywords

3D micro/nanostructure; CeO₂; Organic acid; Inorganic acid; Toluene catalytic combustion