Hierarchical Porous Ceria Synthesized by Maple Leaf Templates and Its Catalytic Performance

doi:10.3724/SP.J.1077.2012.00069

Abstract

Abstract:

Hierarchical porous ceria with nanocrystalline was successfully synthesized using maple leaf as a biotemplate. Unique biomorphic microstructures were characterized by Field Emission Scanning Electron Microscope (FESEM), transmission electron microscope (TEM) and nitrogen absorption-desorption technique. The obtained ceria material shows the repetitious biomimetic structure consisting of the stoma porous about several μm and nanopores with 2-4 nm apertures. The small crystal grain (6-8 nm) and the high specific surface area (64.4 m²/g) of porous CeO₂ are detected by wide-angle X-ray diffraction (XRD), high resolution TEM (HRTEM) and the BET method. The catalytic property is evaluated by the oxygen storage/release capacity (OSC). The test confirms that hierarchical porous material possesses more surface active oxygen than nonporous ceria does. While the concentration of acid fuchsine is 40 mg/L, the porous sample has a higher decoloring rate in a shorter time than others. The decoloring rate can reach 100% after decolored for 300 min. The investigation infers that the hierarchical porous ceria exhibits better catalytic activity and higher adsorptive capacity in dye wastewater purification due to smaller crystallite size, higher surface area and enhanced OSC.

Key words: ceria, hierarchical porous, biotemplate, catalytic activity

CLC Number:

O611
TB321

CHEN Feng, CHEN Zhi-Gang, QIAN Jun-Chao, LIU Cheng-Bao, WANG Wei. Hierarchical Porous Ceria Synthesized by Maple Leaf Templates and Its Catalytic Performance[J]. Journal of Inorganic Materials, 2012, 27(1): 69-73.

Figures/Tables 5

Fig. 1 FESEM images (a, b), TEM image (c) and HRTEM image (d, inset image: SAED pattern) of biomimetic structural hierarchical porous ceria

Fig. 2 XRD patterns of hierarchical porous CeO2 (a) and nonporous CeO2 (b)

Fig. 3 Adsorption-desorption isotherm of N2 (a) for hierarchical porous CeO2 sample and pore size distribution (b) calculated using the BJH method

Fig. 4 Curves of the weight loss for hierarchical porous CeO2 (a) and nonporous CeO2 (b)

Fig. 5 Catalytic degradation activity on acid fuchsine of various samples

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