低维钼基纳米结构材料的可控合成与电催化析氢性能研究

发布时间：2018-03-12 07:17

  本文选题：电催化　切入点：析氢反应　出处：《西北大学》2017年硕士论文　论文类型：学位论文

【摘要】：当前,能源与环境的问题已经影响到了人类的生存和发展。因此,开发出新型的环保能源以取代传统化石燃料是解决这些问题的必由之路。氢能,是一种能量密度高、环保、来源丰富、可再生的新能,被视作取代传统化石燃料的一种理想燃料。目前已经发现的方法中电催化析氢因产量高且环保从而受到了大家的关注。但是已知的性能最好的催化剂Pt储备量太少以及价格太高。因而限制了这种制氢方法的推广。所以,开发出廉价高效的催化剂就是解决问题的关键。目前研究的非贵金属催化剂中,有大量的物质被发现具有作为电催化析氢催化剂的能力。其中Mo基材料因性能优异而备受关注。在本论文中,我们将从钼基材料的角度入手,合成一系列具有一定形貌的钼基的纯化合物及钼基的杂化材料。然后对它们的电催化性能进行测试分析。论文的研究主要有以下的三个部分:(1)采用一个简单的(NH_4)_6Mo_7O_24与胺的合成思路,制造出具有一维棒状结构的MoO_3-EDA。我们对其在空气中灼烧,再在Ar/H2气氛中还原,得到了具有二维结构的MoO_2。在催化析氢的测试中,600℃条件下获得的材料因其较好的结晶性而拥有较好的性能,在过电势为300mV时达到15mA/cm2的电流密度。同时它也具备了很好的稳定性。(2)基于一维MoO_3-EDA,我们合成出一维MoO_2纳米棒。然后我们通过水热的方法在其表面复合上一层MoS_2。在催化性能测试中MoO_2-MoS_2杂化纳米棒展现出了明显优于MoO_2的性能。其中样品MoO_2/S-12-3性能最好,在过电势为-210mV时,电流密度为10mA/cm2。同时它也具备很好的稳定性。(3)我们在还原气氛中高温处理MoO_3-EDA,在不同的处理温度下得到一维的MoC以及一系列一维的Mo/MoC。在析氢的测试中,Mo/MoC展现出了更优于MoC的能力,其中Mo/MoC(700℃)在过电势为-200mV时电流密度能达到51.5 mA/cm2,说明这种杂化结构确实提升了性能。在催化稳定性的测试中,它也表现出了良好的性能。
[Abstract]:At present, the problems of energy and environment have affected the survival and development of human beings. Therefore, it is the only way to solve these problems to develop new environmental energy to replace the traditional fossil fuels. Hydrogen energy is a kind of high energy density and environmental protection. A rich source of renewable new energy, It is regarded as an ideal alternative to traditional fossil fuels. Electrocatalytic hydrogen evolution has attracted much attention because of its high production and environmental protection. But the best known catalyst Pt reserve is too high. Less and too expensive. This limits the promotion of this hydrogen production process. Developing cheap and efficient catalysts is the key to solving the problem. A large number of substances have been found to have the ability to act as catalysts for electrocatalytic hydrogen evolution. Mo-based materials have attracted much attention because of their excellent performance. In this paper, we will proceed from the perspective of molybdenum based materials. A series of molybdenum based pure compounds and molybdenum based hybrid materials were synthesized and their electrocatalytic properties were tested and analyzed. The synthesis of amines, We make Moo _ s _ 3-EDAs with one-dimensional rod structures. We burn them in the air and restore them in the Ar/H2 atmosphere. Moo _ 2 with 2-D structure was obtained. The materials obtained at 600 鈩，

本文编号：1600539