摘要自催化剂出现以来，燃料电池的应用得到了极大的发展，其中的质子交换膜燃料电池（PEMFC）以其高效，洁净的突出特点，成为最具备发展前景的动力电池，然而当下PEMFC主要催化剂为Pt类等贵金属催化剂，Pt类催化剂的高价格严重阻碍了PEMFC的商业化发展，为此，我们需要开发成本低廉，性能高效的非Pt类催化剂代替Pt类催化剂催化氧还原反应（ORR），用以实现大规模商业化。目前的非Pt类催化剂种类繁多，但多数催化剂在大电流（1。23V）工况下其催化活性与Pt类催化剂相比仍有较大差距。石墨烯作为一种新型纳米材料，特殊的单原子层结构使其拥有丰富而特殊的性质。通过元素掺杂，可使其功能化，进而具有良好的催化能力。二硫化钼具有与石墨烯相同的结构，为探寻高效的ORR催化剂，研究不同浓度Ni金属元素掺杂的二硫化钼对催化氧气还原反应的影响是很有意义的，这有利于我们设计并开发新型ORR催化剂。本文在软件Materials Studio的模拟下，采用第一性原理的密度泛函理论，分别对不同浓度的Ni原子掺杂二硫化钼Mo位作为ORR催化剂作了系统的实验，通过分析氧气还原反应中间产物的吸附能和反应过程中发生的能量变化，我们发现Mo位掺杂3个Ni原子的二硫化钼催化剂符合吸附能不能太强以及太弱的要求，并在1。23V的高电势下，具有着较低的热力学能垒，这表明其只需要提供较低的能量，就能促使氧气还原反应的进行。在此，通过掺杂，我们实现了功能化二硫化钼，并表明Mo位掺杂3个Ni原子的二硫化钼催化剂可应用于未来燃料电池阴极催化剂。87297
毕业论文关键词：金属掺杂二硫化钼；氧气还原反应；催化剂；第一性原理





Abstract Since the appearance of catalysts, the appliance of fuel cell has been greatly improved。 For proton exchange membrane fuel cell (PEMFC), due to its high efficiency as well as environmental friendliness, it has become the most promising power battery。 However, the current PEMFC catalysts were the noble transition metal catalysts, such as Pt, the high price seriously hindered the commercialization of PEMFC。 So, developing the alternative catalysts to replace Pt catalysts is highly desirable for the large-scale commercialization。 At present, there are many non-Pt catalysts, but major possess the inferior activity compared with Pt catalysts under the working condition。 Graphene, a new type of nanomaterials, due to the special single atomic layer structure, it possess the unique physicochemical property and has raised our attention。 By means of the elements doping to achieve its functionalization, the doped graphene has good catalytic ability。 In order to search high quality ORR catalysts, the two-dimensional MoS2 with the same structure as grapheme are doped by different concentrations of Ni。 In this paper, based on the simulation of Materials studio, using the density functional theory calculations, the ORR activity of the functional different MoS2 is studied。 By calculating the adsorption energy of ORR intermediate, we find that as 3Ni atoms full replace Mo sites, the catalyst possesses the suitable adsorption ability, since the adsorption energy of the optimal catalysts cannot be too strong or too weak。 Besides the adsorption energy, the thermodynamic energy barriers of the ORR steps are considered。 At the potential of 1。23V, the aforementioned catalyst has the lowest thermodynamic energy barrier among the others。 That is, the MoS2 shows ORR activity through Ni doping, which is benefit for fuel cell in the future。

Keywords: metal doped MoS2; oxygen reduction reaction; catalysts; first-principle calculation

目录


第一章  绪论   1
1。1 能源概述   1
1。2 新能源概述   2 MaterialsStudio二维硫化钼边活性研究:http://www.youerw.com/huaxue/lunwen_131950.html