本工作采用密度泛函理论（DFT）和微观动力学方法研究了不同Rh-Ni合金团簇尺寸的Rh_nNi_n/TiO₂ (n = 1、2、3、4)催化剂上的合成气制乙醇反应。结果表明，Rh₁Ni₁/TiO₂和Rh₃Ni₃/TiO₂能够显著促进CO活化转化及C−C链的形成，并抑制甲烷的生成。其中，Rh₁Ni₁/TiO₂表现出最高的乙醇生成活性和相对选择性。电子性质分析表明，在Rh₁Ni₁/TiO₂催化剂上，合金团簇上Ni原子及载体上Ti和O原子向Rh原子转移的电荷最多，合金团簇上Rh-Ni间相互作用最强，且合金团簇与TiO₂载体间的相互作用也最强，其催化活性最高。在525 K下，从头算分子动力学模拟（AIMD）模拟显示Rh₁Ni₁/TiO₂催化剂具有较高的热稳定性。

The direct conversion of syngas to ethanol on the Rh_nNi_n/TiO₂ (n = 1, 2, 3, 4) catalyst has been investigated by using the density functional theory (DFT) and micro-kinetic methods, in order to elucidate the regulatory mechanism of Rh_nNi_n alloy cluster size-induced metal-support interaction on the catalytic performance of Rh_nNi_n/TiO₂ in the ethanol synthesis. The results indicate that Rh₁Ni₁/TiO₂ and Rh₃Ni₃/TiO₂ can significantly enhance the conversion of CO and the formation of C−C bond and meanwhile inhibit the generation of methane. Rh₁Ni₁/TiO₂ exhibits the highest ethanol production activity and relative selectivity. The electronic property analysis results suggest that Ni atoms on the alloy clusters and Ti and O atoms on the supports transfer the most charge to the Rh atoms on the Rh₁Ni₁/TiO₂ catalyst, which displays the strongest Rh-Ni interaction on the alloy clusters as well as the strongest interaction between the alloy clusters and the TiO₂ support, endowing Rh₁Ni₁/TiO₂ with the highest catalytic activity. In addition, the Ab-initio molecular dynamics (AIMD) simulations at 525 K show that the Rh₁Ni₁/TiO₂ catalyst has high thermal stability.