金属配合物修饰电极析氢性能研究

发布时间：2018-02-12 11:23

本文关键词： 金属配合物碳糊电极电催化析氢　出处：《合肥工业大学》2017年硕士论文　论文类型：学位论文

【摘要】：氢气具有清洁无污染、高效、可储存和运输等优点,被视为最理想的能源载体。析氢电极材料由于存在着过电势高、不稳定等缺点,因此需要研究开发一种具有高析氢催化活性和稳定性及价格低廉的电极材料。金属配合物主要是由金属离子和有机配体两个重要的部分组成,同时兼具无机物和有机物的特点,因具有结构多样、性质多样等特点,广泛应用于光学、吸附、催化等方面。本文中,以过渡金属配合物材料作为析氢电催化剂用来修饰碳糊电极,研究其在酸性介质中的催化性能。首先,以4,4-联吡啶为配体,采用热溶剂法合成W/S/Cu簇合物,制备W/S/Cu簇合物修饰的碳糊电极(W/S/Cu-GPE),并对其结构进行表征。利用阴极极化曲线、电化学阻抗等技术研究W/S/Cu簇合物对该电极催化析氢性能的影响。结果表明,W/S/Cu-GPE电极的开路电势与GPE电极的开路电势相比正移了 0.178 V,并且在同一开路电势下W/S/Cu-GPE的电流密度远远大于GPE电极的电流密度,W/S/Cu-GPE电极的活化能为95.1 kJ mol-1,比GPE电极的活化能降低了 31%。其次,以5-磺基间苯二甲酸单钠盐和1,10-菲咯啉为双配体,采用溶剂热法分别合成Ni(II)、Cu(II)配合物,并对其结构进行表征。制备了 2种配合物修饰的碳糊电极Ni-GPE及Cu-GPE。探索电极材料、温度、催化剂的含量对其析氢催化性能的影响。采用FE-SEM对电极表面形貌进行表征,利用电化学阻抗技术对电极材料析氢界面状况进行分析。结果表明,在电流密度为10mAcm-2时,与GPE电极相比,Ni-GPE电极的析氢过电势正移了 0.203 V,Cu-GPE电极的析氢过电势正移了 0.170 V,其中,Cu-GPE电极的交换密度是GPE电极的13倍。最后,以3,5-吡唑二羧酸,1,10-菲咯啉为配体,采用溶剂热法合成2种双金属CuBi配合物和CuGd配合物,分别制备双金属配合物修饰的碳糊电极CuBi-GPE和CuGd-GPE,并探索电极材料、配体、温度以及催化剂含量对其析氢性能的影响。结果表明,在电流密度为10 mA cm-2时,CuBi-GPE电极的过电势与GPE电极的过电势相比正移了 0.538 V,其交换密度是GPE电极的181倍,CuGd-GPE电极的过电势与GPE电极的过电势相比正移了 0.450 V,其交换密度是GPE电极的1206倍。
[Abstract]:Hydrogen has the advantages of clean, pollution-free, efficient, storage and transportation, and is regarded as the most ideal energy carrier. Hydrogen evolution electrode materials have many disadvantages, such as high potential, instability and so on. Therefore, it is necessary to study and develop an electrode material with high hydrogen evolution activity, stability and low cost. The metal complexes are mainly composed of two important parts, metal ions and organic ligands, and have the characteristics of both inorganic and organic compounds. Because of its diverse structure and properties, it is widely used in optics, adsorption, catalysis and so on. In this paper, transition metal complexes are used as hydrogen evolution electrocatalysts to modify carbon paste electrodes. Firstly, the W / S / Cu cluster was synthesized by thermal solvent method, and the carbon paste electrode modified by W / S / Cu cluster compound was prepared, and its structure was characterized by cathodic polarization curve. The effect of W / S / Cu cluster on the catalytic hydrogen evolution of the electrode was studied by electrochemical impedance spectroscopy. The results showed that the open circuit potential of W / S / Cu -GPE electrode shifted 0.178 V compared with the open circuit potential of GPE electrode, and the W / S / Cu GPE electrode had a positive shift in the open circuit potential of W / S / Cu GPE electrode under the same open circuit potential. The current density is much larger than the current density of GPE electrode. The activation energy of W / S / Cu-GPE electrode is 95.1 kJ mol -1, which is lower than that of GPE electrode. Two kinds of carbon paste electrodes, Ni-GPE and Cu-GPE, were prepared by solvothermal method and their structures were characterized by solvothermal method with sodium 5-sulfoisophthalate and 1-10-phenanthroline as double ligands. FE-SEM was used to characterize the surface morphology of the electrode, and electrochemical impedance technique was used to analyze the hydrogen evolution interface of the electrode material. The results showed that the current density was 10mAcm-2. Compared with GPE electrode, the hydrogen evolution superpotential of Ni-GPE electrode is 0.203V and that of Cu-GPE electrode is 0.170V. the exchange density of Cu-GPE electrode is 13 times that of GPE electrode. Two kinds of bimetallic CuBi complexes and CuGd complexes were synthesized by solvothermal method. The carbon paste electrodes modified by bimetallic complexes, CuBi-GPE and CuGd-GPE, were prepared, and the electrode materials and ligands were explored. The effect of temperature and the content of catalyst on the hydrogen evolution performance. When the current density is 10 Ma cm-2, the overpotential of CuBi-GPE electrode is 0.538 V higher than that of GPE electrode. The exchange density of CuBi-GPE electrode is 181 times of that of GPE electrode. Compared with that of GPE electrode, the overpotential of CuBi-GPE electrode is 0.450 V, and the exchange density of CuBi-GPE electrode is higher than that of GPE electrode. The density is 1206 times higher than that of GPE electrode.
【学位授予单位】：合肥工业大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TQ116.2;O646.5

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