CeO_2形态对CeO_2/Au电极催化氧化乙醇的影响

Effect of Morphology of CeO_2 on Electrochemical Oxidation of Ethanol Run on CeO_2/Au Electrode

利用煅烧和微波诱导燃烧法合成了不同形态的CeO2。利用TG-DSC对前驱物Ce2(CO3)3进行了热分析,结果表明产物为CeO2。分别用XRD,Raman光谱仪,FE-SEM,FT-IR等对产物结构进行了表征。XRD和Raman分析结果证明,产物具有与萤石相似的结构。FT-IR分析表明:在约1382cm-1处为Ce-O键的伸缩震动。FE-SEM照片说明用煅烧法合成的产物比用微波诱导燃烧法合成的产物孔隙率更低。分别用纯金电极、不同形态CeO2修饰的玻碳电极和金电极在1.0mo.lL-1KOH和1.0mol.L-1乙醇的混合液中对乙醇进行电催化氧化实验,结果表明:通过CeO2对金电极的修饰可以提高其催化活性,CeO2的形态会影响电流强度。

CeO2 with different morphology was prepared by calcination and microwave-induced combustion methods. The precursor （ Ce2 （ CO3 ） 3 ） was analyzed by TG-DSC and the result revealed that CeO2 was produced. The samples obtained were characterized by XRD, laser raman spectrum, field-emission scanning electron microscope（FE-SEM） and FT-IR respectively. The results of XRD and Raman showed that all of the as-prepared samples were with fluoritelike structure. FT-IR analysis displayed that the band rised at approximately 1382 cm^-1 was ascribed to the Ce- O stretching vibration. FE-SEM exhibited that porous in the product prepared by calcination was less than that in the product synthesized by microwave-induced combustion process. Electrochemical oxidation of ethanol was run in the mixed solution of 1. 0 mol.L^-1 KOH with 1.0 mol .L^-1 ethanol solution by cyclic voltammetry method taking real Au, glass carbon and Au electrode modified by CeO2 with different morphology as an electrode, respectively. The results showed that the catalytic activities of Au electrode could be improved by modified CeO2 and current intensity could be influenced by the morphology of CeO2.