Methane dry reforming on a Ru(0 0 1) single-crystal surface was investigated using a high-pressure reactor directly combined with an ultra-high-vacuum system for temperatures between 700 and 800 K and under initial CH₄ and CO₂ pressures in a range of 50–240 Pa. In the CH₄–CO₂ reaction, dry reforming (DRM) proceeds accompanied by a quasi-equilibrated reverse water gas shift reaction. The rate of the DRM reaction exhibits first-order dependence on CH₄ pressure and is almost independent of CO₂ pressure, giving an apparent activation energy of 110 kJ/mol. These kinetic parameters are in good agreement with those reported on Ru-supported oxide catalysts. From the exchange reaction between ¹³CO₂ and CO, a very low activation energy of 7.2 kJ/mol and a TOF around 18 are obtained for CO₂ dissociation on the bare Ru(0 0 1) surface. In the CH₄–¹³CO₂ reaction, the exchange reaction between ¹³CO₂ and CO is also quasi-equilibrated. These results are consistent with ultraviolet photoelectron spectroscopy and low-energy electron diffraction measurements for postreaction Ru surfaces, which show that carbon species derived from the decomposition of CH₄ are substantially removed as CO by oxygen atoms supplied from the dissociation of CO₂. Taking the respective reaction orders of CH₄ and CO₂ into consideration, it is concluded that the rate-limiting step for the DRM reaction is the breaking of the CH bond in CH₄.

使用直接与超高真空系统组合的高压反应器，在700至800 K的温度下，在初始CH ₄和CO ₂压力下，研究了Ru（0 0 1）单晶表面上的甲烷干重整。CH ₄ -CO ₂反应的范围为50-240 Pa。在进行干重整（DRM）的同时进行准平衡的反向水煤气变换反应。DRM反应的速率对CH ₄压力表现出一阶依赖性，并且几乎与CO ₂无关压力下，表观活化能为110 kJ / mol。这些动力学参数与Ru-负载的氧化物催化剂上报道的那些动力学参数非常一致。通过¹³ CO ₂和CO之间的交换反应，获得了非常低的7.2 kJ / mol的活化能和18左右的TOF，用于在裸露的Ru（0 0 1）表面上进行CO _2的离解。在CH ₄ – ¹³ CO ₂反应中，¹³ CO ₂之间的交换反应二氧化碳也准平衡。这些结果与用于后反应Ru表面的紫外光电子能谱和低能电子衍射测量结果一致，这表明源自CH ₄分解的碳物质基本上被CO ₂的解离提供的氧原子作为CO除去。考虑到CH ₄和CO ₂各自的反应顺序，可以得出结论，DRM反应的限速步骤是CH _4中C H键的断裂。