二元过渡金属硫属族化物的制备及其电催化产氢性能研究

发布时间：2018-03-19 21:47

本文选题：电解水　切入点：NiMoO_4　出处：《山东大学》2017年硕士论文　论文类型：学位论文

【摘要】：当今世界,人类面临空前增加的能源需求,同时,寻找更加清洁的能源也是人们所关注的话题。人们致力于寻找储量丰富、廉价的能源,从而减小对化石资源的依赖。电解水制备氢气是满足全球能源需要以及环境友好的一种方式。原因是氢气作为清洁可再生的能源,被认为是替代化石能源的最具潜力的新能源。目前制备氢气的方式众多,而电解水制备氢气的方法是大规模制备氢气的主要途径。在电解水制备氢气的过程中,高效的电极材料至关重要。因此制备电催化活性好、过电势低的电极材料是人们目前主要的工作。虽然Pt、Pd等贵金属在电催化析氢反应中有较低的过电势,但是因为贵金属的丰度低、成本高,限制了其大规模使用,因此,研究电催化活性高的非贵金属至关重要。近年来,过渡金属氧化物、碳化物、硫化物以及硒化物引起了人们的广泛关注。本论文利用水热法制备NiMoO_4纳米线阵列和Ni_(0.85)Se/MoSe_2复合材料,并研究其微观形貌和电催化析氢性能,本论文的研究内容主要包括以下两个部分。1:采用水热合成法在泡沫镍上生长一维径向的NiMoO_4纳米线阵列,电化学测试结果表明NiMoO_4纳米线阵列的电催化析氢活性与泡沫镍基底相比,有较明显的提高。在碱性电解质溶液中,要达到j=10mA/cm~2的要求,NiMoO_4纳米线阵列的过电势仅为216 mV,而泡沫镍基底则需要267 mV的过电势才能达到同样的电流密度,电势差为51 mV。而塔菲尔曲线的斜率也差别较大,在相同条件下,NiMoO_4纳米线阵列和泡沫镍基底的tafel斜率分别为109.74 mV dec~(-1)和155.82 mV dec~(-1)。2:采用水热法将NiMoO_4纳米线阵列硒化,制备Ni_(0.85)Se/MoSe_2纳米复合材料,研究其电催化活性。由于电解水制备氢气的过程中需要多步骤的结合,包括吸附、电化学脱附和复合脱附三步骤,使得单组分具有电化学活性的电极材料在电化学产氢的过程中的活性受到了限制,因此我们制备Ni_(0.85)Se/MoSe_2复合材料来提高催化剂的电化学活性。Ni_(0.85)Se/MoSe_2复合材料的起始过电势为21 mV,而NiMoO_4纳米线阵列的起始过电势为106 mV,过电势差近5倍。塔菲尔斜率为83.74 mV dec~(-1),比NiMoO_4纳米线阵列的塔菲尔斜率109.74 mV dec~(-1)低很多,显示了很高的电化学活性,并且电极材料表现出很好的稳定性。本工作为电解水制氢电极材料的研究提供了一种新思路。
[Abstract]:In today's world, mankind is facing an unprecedented increase in energy demand, at the same time, looking for more clean energy is also a topic of concern. People looking for abundant, cheap energy, thereby reducing dependence on fossil resources. Water electrolysis hydrogen preparation is a way to meet the global needs source and friendly environment. Hydrogen as a clean and renewable energy, is considered to be an alternative to fossil energy new energy potential. At present many hydrogen preparation method, and method of water electrolysis hydrogen preparation is the main way for the large-scale production of hydrogen. The size in the process of water electrolysis hydrogen preparation, important efficient electrode material. So the preparation of electro catalytic activity, a low potential electrode material is the most important work. Although Pt, Pd and other precious metals have low overpotential in electrocatalytic hydrogen evolution reaction, but because of your gold Genus of low abundance, high cost, limited its large-scale use, therefore, it is important to study the high electrocatalytic activity of non noble metals. In recent years, transition metal oxides, carbides, sulfides and selenides has attracted widespread attention. The preparation of NiMoO_4 nanowire arrays and Ni_ by hydrothermal method (0.85) Se/MoSe_2 composite materials, and to study its morphology and electrocatalytic hydrogen evolution, the main content of this thesis include the following two parts of NiMoO_4 nanowires.1: by hydrothermal method and one-dimensional radial growth on nickel foam array, electrochemical test results show that compared to the electro catalytic activity of hydrogen evolution and foam nickel substrate of NiMoO_4 nanowires the array, are obviously improved. In alkaline electrolyte solution, to achieve the requirements of the j=10mA/cm~2, the overpotential of NiMoO_4 nanowire arrays is 216 mV, while the nickel foam is required over 267 power base mV In order to achieve the same potential current density, potential is 51 mV. and the slope of the Tafel curve is also quite different, under the same conditions, the slope of Tafel NiMoO_4 nanowire arrays and nickel foam substrate were 109.74 mV and 155.82 mV dec~ (-1) dec~ (-1).2: by hydrothermal method NiMoO_4 selenide nanowire arrays preparation, Ni_ (0.85) Se/MoSe_2 nano composite material, study its electrocatalytic activity. Due to the combination, need to process water electrolysis hydrogen preparation including the adsorption, desorption and desorption electrochemical composite three steps, the single component with active electrode materials of electrochemical activity in the process of electrochemical hydrogen production in is limited, so we prepared Ni_ (0.85) Se/MoSe_2 composite materials to improve the electrochemical activity of.Ni_ catalyst (0.85) initial Se/MoSe_2 composite potential is 21 mV, while the initial column of the NiMoO_4 nanowire arrays have the potential for 1 06 mV, a potential difference of nearly 5 times. Tafel slope is 83.74 mV dec~ (-1), than the Tafel slope of NiMoO_4 nanowire arrays of 109.74 mV dec~ (-1) is much lower, showed high electrochemical activity, and electrode materials show good stability. This work provides a new way for the research of the electrolytic water making hydrogen electrode material.

【学位授予单位】：山东大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：O643.36;TQ116.2

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