金属有机骨架衍生的氮掺杂多孔碳材料的制备及其电催化氧还原性能的研究

发布时间：2018-04-04 20:23

  本文选题：燃料电池　切入点：氧还原反应　出处：《辽宁大学》2017年硕士论文

【摘要】：发展燃料电池(full cells)代替传统的电化学电池,是当今社会科技发展的趋势。燃料电池之所以没有被大规模生产使用,主要是由于燃料电池本身阴极反应的动力学惰性,燃料电池阴极主要发生氧还原反应(oxygen reduction reaction),这其中涉及到气体扩散、吸附、电子转移、产物扩散等等,是一个复杂的过程。所以,提高燃料电池阴极氧还原反应的速率,使用高效的电催化剂是至关重要的。科研人员们在不断研究探索过程中发现:基于Pt的催化剂在目前是对氧还原反应效果最好的电催化剂。然而,Pt基的电催化剂受稳定性限制、燃料交叉的影响、CO中毒等影响,而且Pt本身属于贵金属,在地壳中含量低,成本高,不利于大规模商业化生产。因此,寻找更廉价的电催化剂来代替Pt显得尤为重要,也是当前的科研热点之一。金属有机骨架材料有着以下特点,如:金属与配体的可选择性、比表面积大、孔隙率高且孔径可调控、含碳量高等。本文利用金属有机骨架作为前驱体,合成了两个系列氮掺杂多孔碳材料作为氧还原反应电催化剂,氮掺杂无金属多孔碳材料NPC-800、NPC-900、NPC-1000以及Co纳米粒子负载氮掺杂多孔碳材料Co@NPC-800、Co@NPC-900、Co@NPC-1000。并对这两个系列的多孔碳材料进行电化学性质的研究。结果表明,两种不同类型的碳材料均有氧还原活性。在氮掺杂无金属多孔碳材料中NPC-900不仅N含量较高,石墨化程度高而且电催化活性最好,其起始电位、电流密度、转移电子数在三个样品中是最理想的。金属Co纳米粒子负载的氮掺杂多孔碳材料,也具有非常优越的氧还原活性,Co@NPC-800、Co@NPC-900表现出较好的电催化活性。利用金属有机骨架为前驱体或模板合成多孔碳材料,并对该碳材料进行处理,进而得到不同类型的具有优异的氧还原电催化活性多孔碳,对于提高氧还原反应效率具有一定的研究价值。
[Abstract]:It is the trend of science and technology to develop full fuel cells instead of traditional electrochemical cells.The reason why fuel cells are not used in large-scale production is mainly due to the kinetic inertia of the cathode reaction of the fuel cell itself. The cathode of the fuel cell mainly takes place in oxygen reduction reaction, which involves gas diffusion, adsorption, electron transfer.Product diffusion and so on, is a complex process.Therefore, it is very important to increase the rate of cathodic oxygen reduction reaction and to use efficient electrocatalysts.In the process of continuous research and exploration, the researchers found that Pt based catalyst is the most effective electrocatalyst for oxygen reduction at present.However, Pt-based electrocatalysts are restricted by the stability and the influence of fuel crossover, such as CO poisoning, etc. Moreover, Pt itself belongs to precious metal, which has low content and high cost in the crust, which is not conducive to large-scale commercial production.Therefore, it is very important to find cheaper electrocatalysts to replace Pt.The metal-organic skeleton materials have the following characteristics, such as the selectivity of metal and ligands, large specific surface area, high porosity and adjustable pore size, and high carbon content.鏈�鏂囧埄鐢ㄩ噾灞炴湁鏈洪�ㄦ灦浣滀负鍓嶉┍浣，

本文编号：1711544