【摘要】 利用密度泛函理论研究了巴豆醛和肉桂醛分子在Pt-Ni-Pt(111)面的吸附构型以及相关电子性质.吸附构型与吸附能结果表明,巴豆醛和肉桂醛在覆盖度为1/25 ML的条件下,以C=C和C=O双键协同吸附在Pt-Ni-Pt(111)面较为稳定,且肉桂醛与Pt-Ni-Pt(111)面的吸附能远大于巴豆醛.由Mulliken电荷布局和差分电荷密度可知,在吸附过程中肉桂醛分子向Pt-Ni-Pt(111)面上转移的电荷数较巴豆醛更多,相互作用更大.由电子态密度分析结果可知,不饱和醛与Pt-Ni-Pt(111)面的吸附作用主要是由于分子的p轨道电子与催化剂d轨道电子之间的相互作用.由于苯基的存在使肉桂醛分子在Pt-Ni-Pt(111)面上的吸附更强,且平行于催化剂表面.更多还原

【Abstract】 The adsorption configurations of crotonaldehyde and cinnamaldehyde molecules on Pt-Ni-Pt( 111)surface and their electronic properties were studied with density functional theory( DFT). The adsorption configurations and adsorption energy values illustrate that synergistic adsorption of crotonaldehyde and cinnamaldehyde molecules on Pt-Ni-Pt( 111) surface with C=O and C=C bonds are most stable under the coverage of 1/25 ML. Moreover,the adsorption energy values of cinnamaldehyde on Pt-Ni-Pt( 111) surface are much larger than that of crotonaldehyde. By analyzing Mulliken atomic charge population and the deformation density,it is found that the cinnamaldehyde molecule transfers more electrons to the Pt-Ni-Pt( 111)surface and interact more strongly. The result of partial density of states( PDOS) indicates that the main reason for the adsorption is due to the interaction of the p orbital electrons of the unsaturated aldehyde molecules with the d orbital electrons of metal surface. And,due to the presence of the phenyl group,the cinnamaldehyde molecule is parallel to the surface of the Pt-Ni-Pt( 111) and adsorbed more strongly.更多还原