摘要
运用密度泛函理论中广义梯度近似的PW91方法结合周期平板模型,研究了NiFeB2合金簇在TiO2(110)面的吸附模式.结果表明,NiFeB2平行吸附在TiO2面的Ot-Ot位最稳定,吸附能为526.4kJ/mol.为了探明NiFeB2/TiO2是否具有催化氧化CO活性,进一步研究了CO和O2在NiFeB2/TiO2面的共吸附行为.结果表明,CO和O2以Eley-Rideal机理共吸附在Fe上时,易形成碳酸盐,而以Langmuir-Hinshelwood机理共吸附在Fe上时,O2发生分解,与Fe,Ni和B形成稳定的六元环.
The loaded modes of NiFeB2 supported on the TiO2（110） surface were studied with a periodic slab model by PW91 approach of GGA within the framework of density functional theory. The results of geometry optimization indicated that the most stable adsorption site was NiFeB2 cluster parallel to the Ot-Ot site with an adsorption energy of 526.4 kJ/mol. In order to investigate whether the NiFeB2/TiO2 had the catalytic activity for CO oxidation, the co-adsorption of CO and O2 molecules on NiFeB2 /TiO2 surface was studied. The results showed that the CO and O2 were co-adsorbed on the Fe site by the Eley-Rideal mechanism to form carbonate. When the CO and O2 were co-adsorbed on the Fe site by the Langmuir-Hinshelwood mechanism, the oxygen decomposed and bonded with Fe, Ni, and B atoms, forming a stable six-membered ring.
出处
《催化学报》
SCIE
EI
CAS
CSCD
北大核心
2010年第4期423-428,共6页
基金
国家自然科学基金(90922022
10676007
20773025)
福建省高等学校新世纪优秀人才计划(HX2006-103
HX2006-97)
华中科技大学煤燃烧国家重点实验室开放基金(FSKLCC0814)
福州大学科技基金(2008-XQ-07
XRC-0732)
关键词
密度泛函理论
吸附
非晶态合金
二氧化钛
一氧化碳
氧
density functional theory
adsorption
amorphous alloy
titania
carbon monoxide
oxygen
