物理学报
物理學報
물이학보
2013年
7期
364-369
,共6页
罗强%唐斌%张智%冉曾令
囉彊%唐斌%張智%冉曾令
라강%당빈%장지%염증령
第一性原理%Fe(100)表面%吸附能%硫化氢
第一性原理%Fe(100)錶麵%吸附能%硫化氫
제일성원리%Fe(100)표면%흡부능%류화경
first principles%Fe(100) surface%adsorption energy%hydrogen sulfide
基于密度泛函理论第一性原理,在广义梯度近似下,研究了表面覆盖度为0.25 ML (monolayer)时硫化氢分子在Fe(100)面吸附的结构和电子性质,并与单个硫原子吸附结果进行了对比.结果表明:硫化氢分子吸附在B2位吸附能最小为?1.23 eV,最稳定, B1位吸附能最大为?0.01 eV,最不稳定;并对硫化氢分子在B1位和B2位吸附后的电子态密度进行了分析,也表明了吸附在B2位稳定,且吸附在B2位后硫化氢分子几何结构变化不大;将硫化氢中硫原子吸附与单个硫原子吸附的电子性质进行了比较,发现前者吸附作用非常微弱;同时对吸附后的Fe(100)面进行了对比,单个硫原子吸附的Fe(100)面电子态密度出现了一系列峰值且离散分布,生成了硫化亚铁,表明在硫化氢环境下,主要是硫化氢析出的硫原子发生了吸附.
基于密度汎函理論第一性原理,在廣義梯度近似下,研究瞭錶麵覆蓋度為0.25 ML (monolayer)時硫化氫分子在Fe(100)麵吸附的結構和電子性質,併與單箇硫原子吸附結果進行瞭對比.結果錶明:硫化氫分子吸附在B2位吸附能最小為?1.23 eV,最穩定, B1位吸附能最大為?0.01 eV,最不穩定;併對硫化氫分子在B1位和B2位吸附後的電子態密度進行瞭分析,也錶明瞭吸附在B2位穩定,且吸附在B2位後硫化氫分子幾何結構變化不大;將硫化氫中硫原子吸附與單箇硫原子吸附的電子性質進行瞭比較,髮現前者吸附作用非常微弱;同時對吸附後的Fe(100)麵進行瞭對比,單箇硫原子吸附的Fe(100)麵電子態密度齣現瞭一繫列峰值且離散分佈,生成瞭硫化亞鐵,錶明在硫化氫環境下,主要是硫化氫析齣的硫原子髮生瞭吸附.
기우밀도범함이론제일성원리,재엄의제도근사하,연구료표면복개도위0.25 ML (monolayer)시류화경분자재Fe(100)면흡부적결구화전자성질,병여단개류원자흡부결과진행료대비.결과표명:류화경분자흡부재B2위흡부능최소위?1.23 eV,최은정, B1위흡부능최대위?0.01 eV,최불은정;병대류화경분자재B1위화B2위흡부후적전자태밀도진행료분석,야표명료흡부재B2위은정,차흡부재B2위후류화경분자궤하결구변화불대;장류화경중류원자흡부여단개류원자흡부적전자성질진행료비교,발현전자흡부작용비상미약;동시대흡부후적Fe(100)면진행료대비,단개류원자흡부적Fe(100)면전자태밀도출현료일계렬봉치차리산분포,생성료류화아철,표명재류화경배경하,주요시류화경석출적류원자발생료흡부.
In contrast to the results of sulfur atom adsorption, the adsorption of hydrogen sulfide on the Fe(100) surface has been studied using first principles method, which is based on the density functional theory (DFT). The structures, electronic properties were calculated by the generalized gradient approximation (GGA) for the coverage of 0.25 monolayer (ML). The results show that the H2S adsorbed on B2 site is stable and the adsorption energy is?1.23 eV and the structure of H2S is little changed. While the density of states (DOS) for the adsorption of hydrogen sulfide in the most unstable state after the adsorption at B1 and most stable adsorption at the site of B2 are analyzed. We have compared, under same conditions, the electronic properties of the sulfur atoms of the adsorbed hydrogen sulfide and a single sulfur atom adsorbed on Fe(100) surface. The adsorption effect is very weak for sulfur atoms in adsorbed hydrogen sulfide. At the same time, the density of states for the adsorption of Fe(100) surface was studied comparatively, and we found that the sulfur atom adsorption on Fe(100) showed a series of peaks that have discrete distributions generated by ferrous sulfide. It shows that the adsorption is given by sulfur atoms instead of molecules of hydrogen sulfide.