Adsorption of alkali metal atoms on germanene: A first-principles study

Release time:2024-08-09  Hits:

• Affiliation of Author(s):理学院
• Journal:Applied Surface Science
• Key Words:中文关键字：锗烯; 碱金属; 吸附; 电子结构，英文关键字：Germanene; Alkali metal; Adsorption; Electronic st
• Abstract:The structural, energetic and electronic properties of alkali metal (AM) atoms (including Li, Na and K)adsorbed germanene with a wide range of coverages are investigated by means of first-principles calculations. All AM atoms we considered prefer to bind on the hexagonal hollow site of germanene. Incontrast to graphene, the interaction between adatom and germanene surface is quite strong due to its buckled hexagonal structure. As the increasing adatom coverage, the binding between AM atom and germanene sheet is weakened, due to the enhanced adatom–adatom repulsion while the decreased adatom-germanene attraction at high coverage. As a consequence of heavy charge transfer from AMto germanene, the formed adatom–Ge bonds perform mainly an ionic character. Through adsorption,the semimetallic germanene becomes to be metallic with its Dirac point moving below the Fermi level,thus making germanene behave as n-type doped. In addition, a small band gap can be opened at the Dirac point, and both the band gap and the concentration of charge carries of AM/germanene systemcan be tuned by controlling the adatom coverage. The strong binding of AM adatoms to germanene andthe rich electronic properties of the AM/germanene systems suggest possible potential applications ingermanene based field effect transistor (FET) devices.
• Note:SCI （二区）
• Co-author:魏秀梅,宋玉玲
• First Author:fuzhiqiang,lilong,zhangchunling,pangqing
• Indexed by:Journal paper
• Volume:卷：314
• Issue:期：
• Page Number:页：15-20
• Translation or Not:no
• Date of Publication:2014-09-01