Aseries of Pt/C,Pt-Ni1/3/C,Pt-SnO2/C and Pt-Nix-SnO2/C (x =1/4,1/3,2/3,1) anode electro-catalysts have been synthesized by an improved B(o)nnemann method.The crystal structure,surface morphology and surface electronic structure were characterizated by X-ray diffraction (XRD),high resolution transmission electron microscope (HR-TEM) and X-ray photoelectron spectroscopy (XPS).The electro-catalytic activities were characterizated by linear sweep voltammetry (LSV) and amperometric current density-time (j-t) curve techniques for ethanol oxidation reaction (EOR).In situ spectroelectrochemical studies have been used to identity adsorbed reaction intermediates and products (in situ Fourier transform infrared spectroscopy,FT-IR).XRD and HR-TEM analysis revealed two phases in the ternary Pt-Ni-SnO2/C catalyst:Pt-Ni alloys and SnO2.XPS results show that the electronic structure of the Pt in Pt-Ni1/3-SnO2/C might be changed due to the addition of Ni.The activity of Pt-Ni-SnO2/C for EOR was found to be higher than that of Pt/C,Pt-Ni/C and Pt-SnO2/C catalysts.The incorporation of Ni and SnO2 did not significantly improve C-C bond breaking for complete oxidation of ethanol,but the synergy under the low potential (0.1 V) to strengthen the further oxidation of acetaldehyde,generate the acetic acid.%采用改进的B(o)nnemann法成功制备了Pt/C、Pt-Ni1/3/C、Pt-SnO2/C、Pt-Nix-SnO2/C(x=1/4,1/3,2/3,1)阳极电催化剂.利用X射线衍射(XRD)、高分辨透射电子显微镜(HR-TEM)以及X射线光电子能谱(XPS)对催化剂晶型结构、表面形貌和表面电子结构进行了表征.运用线性扫描伏安(LSV)和电流密度-时间(j-t)曲线进行电化学测试,研究了乙醇电催化氧化(EOR)活性.并用原位红外光谱(in situ FT-IR)研究了EOR过程中产物的分布.结果表明,Pt-Ni1/3-SnOJC是由Pt-Ni合金和SnO2两相组成.XPS结果表明,在Pt-SnO2中添加微量的Ni,Pt表面电子结构发生了改变.电化学结果表明,三元催化剂的EOR活性均优于二元和纯Pt,其中Pt-Ni1/3-SnO2/C的EOR活性最佳.Ni和SnO2的加入并没有显著提高乙醇C-C键的断裂能力,但是二者的协同作用在低电位(0.1 V)下加强了乙醛的进一步氧化,生成了乙酸.
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