HCOOH在电极Pd(110)表面电吸附的密度泛函研究  

Density functional theory study of the electrosorption of formic acid on the Pd(110)electrode surface

作　　者：郭玉宝[1] 朱红[2] 杨儒[2] 

机构地区：[1]北京交通大学理学院,北京100044 [2]北京化工大学化工资源有效利用重点实验室,北京100029

出　　处：《北京交通大学学报》2016年第2期120-124,共5页JOURNAL OF BEIJING JIAOTONG UNIVERSITY

基　　金：国家自然科学基金重点资助项目(20636060);国家自然科学基金资助项目(50674006);北京市自然科学基金重点资助项目(2051001)

摘　　要：采用密度泛函理论和周期平板模型相结合方法,对HCOOH分子在Pd(110)表面bridge,bidentate和unidentate三种形态吸附位进行吸附结构、Mulliken布居和振动频率等性质的计算;计算结果表明HCOOH在金属态表面bidentate为最稳定的吸附位,电极表面unidentate为最稳吸附位;HCOOH在电极表面的吸附远大于金属态表面的吸附能,表明电化学反应比普通化学反应容易进行.电极表面吸附的结构和频率分析显示,吸附过程中O—H、C—H键均伸长,v(O—H)键和v(C—H)振动频率均发生明显红移,表明H原子在吸附过程中容易断裂,脱离HCOOH分子.Mulliken电荷布居分析表明在电吸附过程中电子由HCOOH分子向Pd(110)表面进行转移,有利于电催化反应进行.The density functional theory （DFT） and self-consistent periodic calculation were used to optimize structures, analysis Mulliken population, and calculate vibrational frequency of HCOOH on three possible sites （bridge, bidentate, unidentate） on Pd（ll0） surface . The com- puted results show that. the bidentate site is the preferred adsorption site on metal surface, the unidentate site is the preferred adsorption site on electrode surface. The adsorption energy of HCOOH on the surface of the electrode is greater than the metal surface. The bond length of O- H and C--H has elongated. The vibration frequency of v （O--H） and v （C--H） has decreased.H is easy to break,and divorced from HCOOH in the adsorption process. Mulliken population anal- ysis shows that the electron of HCOOH has transferred into the Pd （110） electrode surface.The results of calculation show that the electro-catalysis is easier than the ordinary chemical reactions of the HCOOH on Pd（110） surface.

关 键 词：Pd(110)表面 甲酸 电吸附 密度泛函理论 

分 类 号：O64[理学—物理化学]