Phase transformation in CeO2–Co3O4 binary oxide under reduction and calcination pretreatments |
| |
Authors: | Chih-Wei Tang Wen-Yueh Yu Chin-Jung Lin Chen-Bin Wang Shu-Hua Chien |
| |
Affiliation: | (1) Department of Applied Chemistry and Materials Science, Chung Cheng Institute of Technology, National Defense University, Tahsi, Taoyuan, 33509, Taiwan, ROC;(2) Institute of Chemistry, Academia Sinica, Taipei, 11529, Taiwan, ROC;(3) Department of Chemistry, National Taiwan University, Taipei, 10617, Taiwan, ROC |
| |
Abstract: | The CeO2–Co3O4 binary oxide was prepared by impregnation of the high surface area Co3O4 support (S.A. = 100m2 g−1) with cerium nitrate (20 wt% cerium loading on Co3O4). Pretreatment of CeO2–Co3O4 binary oxide was divided both methods: reduction (under 200 and 400 °C, assigned as CeO2–Co3O4–R200 and CeO2–Co3O4–R400 and calcination (under 350 and 550 °C, assigned as CeO2–Co3O4–C350 and CeO2–Co3O4–C550). The binary oxides were investigated by means of X-ray diffraction (XRD), nitrogen adsorption at −196 °C, infrared
(IR), transmission electron microscopy (TEM), diffuse reflectance spectroscopy (DRS) and temperature programmed reduction
(TPR). The results showed that the binary oxides pretreatment under low-temperatures possessed larger surface area. The cobalt
phase of binary oxides also was transferred upon the treating temperature, i.e., the CeO2–Co3O4–R200 binary oxide exhibited higher surface area (S.A. = 109m2 g−1) and the main phase was CeO2,Co3O4 and CoO. While, the CeO2–Co3O4–R400 binary oxide exhibited lower surface area (S.A. = 40m2 g−1) and the main phase was CeO2, CoO and Co. Apparently, the optimized pretreatment of CeO2–Co3O4 binary oxide can control both the phases and surface area. |
| |
Keywords: | CeO2– Co3O4 binary oxide phase transformation X-ray diffraction |
本文献已被 SpringerLink 等数据库收录! |
|