The University of Sydney, Faculty of Engineering and Information Technologies, School of Chemical and Biomolecular Engineering, NSW 2006, Australia.
Phys Chem Chem Phys. 2018 Oct 10;20(39):25314-25323. doi: 10.1039/c8cp04066d.
The effect of surface coverage of species, θ, on the kinetic parameters of N2, NO and N2O formation in a system simulating ammonia oxidation over Pt(111) has been studied by using periodic density functional theory (DFT). The energy barriers for product formation decrease as θ increases, with the effect being more significant above 0.25 ML. The heat of surface reaction decreases as θ increases, making the dissociation of the products less favourable due to a weaker interaction of the intermediates with the surface. The effect of θ on the binding energy is stronger for N* than for either O* or NO*, but it is more apparent in the co-adsorption with O* and NO*. Similarly, the coverage of N* more strongly affects the activation energy of N2 and N2O desorption than does the coverage of O* for NO* and N2O formation.
采用周期性密度泛函理论（DFT）研究了在模拟氨氧化过程中 Pt(111)表面物种覆盖率θ对 N2、NO 和 N2O 形成的动力学参数的影响。随着θ的增加，产物形成的能垒降低，在超过 0.25 ML 时，效果更为显著。随着θ的增加，表面反应的热降低，由于中间体与表面的相互作用减弱，产物的离解变得不利。θ对 N的结合能的影响比对 O或 NO的影响更强，但在与 O和 NO的共吸附中更为明显。同样，N的覆盖率对 N2 和 N2O 脱附的活化能的影响比 O对 NO和 N2O 形成的影响更强。
