Ratio screening of high performance Rh-Ni catalyst for ethanol synthesis from syngas: An integration of theoretical and experimental investigation

The direct conversion of syngas to ethanol faces challenges due to catalyst inefficiencies and low ethanol yield. Bulk alloys with an appropriate atomic ratio can exhibit excellent catalytic performance. In this work, a series of Rh x Ni y (111) with different Rh/Ni ratios was rationally designed, and the ethanol preparation from syngas was explored based on density functional theory (DFT) calculation and microkinetic analysis. The results show that Rh 1 Ni 1 (111) was screened out to show optimum catalytic performance for ethanol production. This was attributed to a moderate quantity of charge transfer from Ni to Rh atoms, and a medium distance from the d -band center to the Fermi level. Further, to verify the catalytic performance of the catalysts at a Rh: Ni ratio of 1: 1, 1Rh1Ni/γ-Al 2 O 3 catalyst was prepared and its catalytic performance for ethanol preparation from syngas was investigated by comparing it with that of Rh/γ-Al 2 O 3 and Ni/γ-Al 2 O 3 . The catalytic performance of 1Rh1Ni/γ-Al 2 O 3 has been further confirmed to be preferred over Rh/γ-Al 2 O 3 and Ni/γ-Al 2 O 3 , achieving a 23.0 % CO conversion rate with 31.2 % ethanol selectivity.