First-principles study of co-adsorption behavior of O_(2)and CO_(2)molecules onδ-Pu(100)surface  

作　　者：Chun-Bao Qi Tao Wang Ru-Song Li Jin-Tao Wang Ming-Ao Qin Si-Hao Tao 戚春保;王涛;李如松;王金涛;秦铭澳;陶思昊(Xi'an Research Institute of High Technology,Xi'an 710025,China;Xi'an Jiaotong University,Xi'an 710049,China)

机构地区：[1]Xi'an Research Institute of High Technology,Xi'an 710025,China [2]Xi'an Jiaotong University,Xi'an 710049,China

出　　处：《Chinese Physics B》2021年第2期431-441,共11页中国物理B（英文版）

摘　　要：First principles calculation is performed to study the co-adsorption behaviors of O_(2)and CO_(2)onδ-Pu(100)surface by using a slab model within the framework of density functional theory(DFT).The results demonstrate that the most favorable co-adsorption configurations are T_(v)-C_(4)O_(7)and T_(p1)-C_(2)O_(8),with adsorption energy of-17.296 e V and-23.131 e V for CO_(2)-based and O_(2)-based system,respectively.The C and O atoms mainly interact with the Pu surface atoms.Furthermore,the chemical bonding between C/O and Pu atom is mainly of ionic state,and the reaction mechanism is that C 2 s,C 2 p,O 2s,and O 2p orbitals overlap and hybridize with Pu 6 p,Pu 6 d,and Pu 5 f orbital,resulting in the occurrence of new band structure.The adsorption and dissociation of CO_(2)molecule are obviously promoted by preferentially occupying adsorbed O atoms,therefore,a potential CO_(2)protection mechanism for plutonium-based materials is that in CO_(2)molecule there occurs complete dissociation of CO_(2)→C+O+O,then the dissociated C atom combines with O atom from O_(2)dissociation and produces CO,which will inhibit the O_(2)from further oxidizing Pu surface,and slow down the corrosion rate of plutoniumbased materials.

关 键 词：adsorption energy density functional theory electron density reaction mechanism 

分 类 号：O647.3[理学—物理化学]