One of the rate limiting steps in catalytic ammonia synthesis is a nitrogen dissociation on a catalyst surface, which can be promoted by vibrational excitation of nitrogen molecules. In this work, the efficiency of plasma assisted heterogeneous nitrogen activation via vibrational excitation on the Ru surface is investigated. The analysis consists of two parts: in the first, ab initio calculations are performed for the adsorption and dissociation energy pathways of \({\text{N}}_{{\text{2}}}\) on terrace and step sites and heterogeneous vibrational energy relaxation time of adsorbed nitrogen molecule is calculated using ab initio molecular dynamics. The second part includes the solution of the chemical kinetic equations for vibrationally excited molecules both in the gas phase and on the surface, and an estimation of energy cost of heterogeneous plasma activation of nitrogen. It is shown that heterogeneous vibrational energy relaxation of nitrogen molecule on the Ru surface is rather fast, and results in relatively high energy cost of vibrational nitrogen activation, which is 16 eV/molec for atmospheric pressure and 5 eV/molec for P = 4 Torr according to our calculations.

催化氨合成中的限速步骤之一是催化剂表面上的氮离解，这可以通过氮分子的振动激发来促进。在这项工作中，研究了通过在 Ru 表面上的振动激发等离子体辅助异质氮活化的效率。分析由两部分组成：首先，对\({\text{N}}_{{\text{2}}}\)的吸附和解离能量路径进行了从头算计算使用 ab initio 分子动力学计算在梯田和台阶位置上吸附的氮分子的异质振动能量弛豫时间。第二部分包括气相和表面振动激发分子的化学动力学方程的解，以及对氮异质等离子体活化的能量成本的估计。结果表明，Ru表面氮分子的异质振动能量弛豫速度相当快，导致振动氮活化的能量成本相对较高，大气压下为16 eV/molec，P = 4 Torr时为5 eV/molec根据我们的计算。