论文标题
锂在半金属γ-元素纳米片中的快速插入：一种用于锂离子电池施用的新型IV单钙化物
Fast Intercalation of Lithium in Semi-Metallic γ-GeSe Nanosheet: A New Group-IV Monochalcogenide for Lithium-Ion Battery Application
论文作者
论文摘要
范德华缝隙的存在使锂的二维（2D）材料理想用作阳极材料。但是，良好电导率的要求显着限制了2D候选者的选择。到目前为止，由于其相对较高的电导率，只有石墨才能满足。最近，事实证明，新的硒属（Gamma-gese）的新多晶型物在其散装相中是半学的，其电导率高于石墨，而单层表现为半导体。在这项工作中，通过使用第一原理计算，我们检查了使用这种新的IV单钙化物Gampogenide Gamma-gese作为锂离子电池（LIBS）中的阳极的可能性。我们的研究表明，李原子将在空心部位形成带有相邻的硒原子的离子吸附，并且存在于阳离子状态（丢失了0.89 e，gamma-gese）。攀爬图像螺纹弹性带的结果表明，单层极限中LI的扩散屏障为0.21 eV，即使在伽马 - 基因表面上的室温下，也可以激活相对快速的扩散。计算出的理论平均电压在不同体积变化的不同化学计量时在0.071至0.015 V范围内，这表明其潜在的应用是LIBS的阳极。预测的中度结合能，低的开路电压（与石墨相当）和LI的快速运动表明，伽马 - 基地的纳米片可以通过LI插入化学去化学去角质，并且可以作为LIB的阳极材料作为LIBS的阳极材料进行化学去除。
Existence of van der Waals gaps renders two-dimensional (2D) materials ideal passages of lithium for being used as anode materials. However, the requirement of good conductivity significantly limits the choice of 2D candidates. So far only graphite is satisfying due to its relatively high conductivity. Recently, a new polymorph of layered germanium selenide (Gamma-GeSe) was proven to be semimetal in its bulk phase with a higher conductivity than graphite while its monolayer behaves semiconducting. In this work, by using first-principles calculations, we examined the possibility of using this new group-IV monochalcogenide, Gamma-GeSe, as anode in the Li-ion battery (LIBs). Our studies revealed that Li atom would form an ionic adsorption with adjacent selenium atoms at the hollow site and exist in cationic state (lost 0.89 e to Gamma-GeSe). Results of climbing image-nudged elastic band show the diffusion barrier of Li is 0.21 eV in the monolayer limit, which can activate a relatively fast diffusion even at room temperature on the Gamma-GeSe surface. The calculated theoretical average voltages range from 0.071 to 0.015 V at different stoichiometry of LixGeSe with minor volume variation, suggesting its potential application as anode of LIBs. The predicted moderate binding energy, a low open circuit voltage (comparable to graphite) and a fast motion of Li suggests that Gamma-GeSe nanosheet can be chemically exfoliated via Li intercalation and a promising candidate as the anode material for LIBs.
