Li原子修饰缺陷蓝磷单层储氢性能的第一性原理研究

本文基于第一性原理计算,系统地研究了碱金属Li原子修饰缺陷蓝磷单层体系的储氢性能. 研究结果表明,双空位缺陷DV2的引入可以有效增强Li原子与蓝磷单层间的相互作用,能够有效阻止单层表面Li团簇的形成. 单个Li原子可以稳定吸附3个H2分子,H2分子平均吸附能为0.248 eV/H2. 电子结构分析表明,H2分子主要通过极化机制和轨道杂化作用吸附在Li修饰的缺陷蓝磷单层体系上. 此外,本文还研究了温度和压强对Li/DV2体系储氢性能的影响. 结果表明,在室温和低压条件下,H2分子可以稳定吸附在Li/DV2体系表面,从而实现室温条件下的可逆储氢.

First-principles study on hydrogen storage property of Li-decorated defective blue phosphorene monolayer

The hydrogen storage properties of defective blue phosphorene monolayer decorated by alkali metal Li were systematically investigated by using first-principles calculations. The results show that the interaction between Li atom and blue phosphorene monolayer can be enhanced by introducing the double -vacancy defect DV2, thus hindering effectively aggregation of Li on the surface of the blue phosphorene monolayer. Three H2 molecules can be absorbed by a Li atom with the average adsorption energy of 0.248 eV/H2. Both the polarization mechanism of H2 molecules and the weaker hybridization of Li-s/p orbitals with H-s orbitals are responsible for the adsorption of H2 molecules. The effect of temperature and pressure on the hydrogen storage performance is also investigated, and the results indicate that the H2 storage systems can be stable at room temperature and low pressure, and thus the practical reversible hydrogen storage can be achieved at room temperature.