N_2O在Cu/t-ZrO_2(101)表面的吸附与解离

Adsorption and Decomposition of N_2O on Cu/t-ZrO_2(101) Surfaces

运用广义梯度密度泛函理论结合周期性平板模型方法研究了N2O在完整及负载Cu的四方相ZrO2(101)表面的吸附与解离.结果表明,N2O在完整ZrO2(101)表面的吸附均为物理吸附,Cu在其完整表面的次表层第一氧位为最稳定吸附位,且覆盖度为0.25ML时的吸附最为稳定,吸附能为155.8kJ/mol;N2O分子中O端弱物理吸附于Cu/ZrO2(101)表面,其N端及平行吸附方式得到的稳定吸附能分别为121.6和66.8kJ/mol.频率及电荷布居计算表明,吸附后对称和反对称伸缩振动频率均发生红移,电子由Cu负载底物表面转移给N2O分子.对N2O分子的解离考虑了N端垂直吸附和平行吸附两种解离反应过程,发现平行吸附过程的解离更易发生.

The density functional theory and slab models have been applied to investigate the adsorption and dissociation of N2O on perfect t-ZrO2（101） and Cu/t-ZrO2（101） surfaces.The results indicated that N2O adsorption on the ZrO2（101） surface is physical adsorption.The first of sub-surface oxygen site is the most stable adsorption site for the Cu/ZrO2（101） surface,and when the coverage is 0.25 ML,the most stable models were obtained with adsorption energy of 155.8 kJ/mol.The adsorption of N2O on the Cu/t-ZrO2（101） surface by O-end is weak physical adsorption,and the N-end and parallel adsorption energy is 121.6 and 66.8 kJ/mol,respectively.Vibrational frequency and the Mulliken population were calculated,and the results indicated that the symmetric and antisymmetric vibrational frequencies are red-shifted and the charge transfers from Cu/t-ZrO2（101） to N2O after adsorption.The N-end and parallel dissociation process were considered and the parallel dissociation process is more feasible.