UCLA

DFT-based modeling of Ni2In3 (110) and NiSi2 (101) intermetallic surfaces was used to describe surface chemistry during acetylene hydrogenation and oligomerization reactions. The adsorption energies of partially and completely isolated Ni active sites were investigated in Ni2In3 and NiSi2, respectively. The activity and selectivity of the catalysts were benchmarked against monometallic Ni surface. Despite the weak adsorption of acetylene and ethylene on the Ni2In3 (110), selectivity toward ethylene was not enhanced. Acetylene oligomerization was favorable on Ni2In3 (110) and competed with acetylene hydrogenation. NiSi2 (101) exhibited strong acetylene adsorption and suppressed green oil formation. Hydrocarbon molecules on NiSi2 (101) were activated by Si and Ni atoms, while In atoms showed low activity toward hydrogen and hydrocarbon molecules.