单层C2N做为离子电池阳极材料的理论研究

摘要 21世纪手机等移动电子设备的崛起，带动了二次电池领域的进步。锂离子电池和钠离子电池因能量密度高、循环寿命高、无污染等特点，具有很广阔的应用前景。提升二次电池电容量和充放循环率的关键技术之一就是开发稳定高效的电极材料。本论文系统地评估了一种新奇的二维多孔材料——C2N作为离子电池阳极材料的应用前景。运用密度泛函计算方法，我们计算并确定了Li离子电池和Na离子电池的吸附能和电池容量，采用分子动力学模拟证明了300 K时饱和吸附的C2N结构热力学稳定性，并通过分波态密度和差分电荷密度分析阐明了Li和Na的吸附机理。饱和吸附时的平均结合能分别为2。54 eV和1。95 eV，均大于Li和Na块体的粘合能1。60 eV和1。14 eV，这能够有效地避免金属原子在材料表面团聚。这些研究对于C2N的大规模应用提供了一定的指导作用。87443

毕业论文关键词离子电池多孔C2N结构密度泛函理论第一性原理分子动力学

毕业设计说明书外文摘要

Title Theoretical Study of Monolayer C2N As the Anode Material of Ion Battery

Abstract In the 21st century, the development of mobile electronic devices, such as cell phones, drives the progress of the rechargeable batteries。 Li and Na ions batteries have a broad application prospect, because of their high energy density, long cycle life, and environmentally friendly property, etc。 The key of ion battery application is to develop an economic and efficient electrode material which can obtain enough capacity to satisfy the practical requirements。 In this dissertation, two-dimensional porous C2N structure was taken as the anode material in Li and Na ions batteries。 By using density functional theory calculations, we have calculated and determined the binding energies and specific capacities of Li and Na adsorbed on C2N。 The Li10@C2N and Na9@C2N show good thermal stability by first-principles molecular dynamics simulations at 300 K。 The adsorption mechanism was elucidated by analyzing the partial density of states and charge density differences。 The average binding energy of adsorbed Li and Na atoms of Li10@C2N and Na9@C2N are 2。54 and 1。95 eV, respectively, which are much larger than the cohesive energy per atom of bulk Li (1。60 eV) and Na (1。14 eV)。 These values are ideal for atomically dispersed Li or Na doping in experiments which can avoid the metal clustering problems。 These studies provided theoretical guidance for the large-scale application of C2N as the anode material of ion battery。

Keywords: ion battery porous C2N structure density functional theory first principles molecular dynamics

第一章绪论 -1-源-于Y优+尔-论.文:网www.youerw.com 原文+QQ7520^18766

1。1 引言 -1-

1。2锂离子电池及其电极材料的研究现状 - 1-

1。3钠离子电池及其电极材料的研究现状 -4-

第二章理论计算基础 -6-

2。1 第一性原理 -6-

2。1。1 物理模型的三个近似 -7-

2。2 密度泛函理论 -8-

2。2。1 Hohenberg-Kohn定理 -9-

2。2。2 Kohn-Sham方程 -9-

2。3 分子动力学模拟 -11-

2。4 计算软件包简介单层C2N做为离子电池阳极材料的理论研究:http://www.youerw.com/wuli/lunwen_137340.html