The effects of doping metal type and ratio on the catalytic performance of C2H2 semi-hydrogenation over the intermetallic compound-containing Pd catalysts

Abstract

IMCs-containing Pd show excellent catalytic performance toward C2H2 semi-hydrogenation and a long-term stability, however, the effects of doping metal type and ratio for IMCs-containing Pd on the catalytic performance is still unclear. In this work, C2H2 semi-hydrogenation on PdM(M = Cu, Ag, Au) IMCs with Pd/M ratio of 1/3, 1/1 and 3/1 are studied using DFT calculations. The results indicate that Pd1Cu3, Pd1Ag1 and Pd1Au1 IMCs catalysts show better activity and selectivity toward C2H4 formation and inhibit the formation of green oil (the liquid part of C4+ hydrocarbons), especially, PdCu is better than PdAg and PdAu. Among these catalysts, PdCu3 with surface isolated Pd atom as active sites is the most suitable considering the cost and catalytic performance. This work gives out valuable clues for the design of IMCs-containing Pd catalysts in C2H2 semi-hydrogenation, which have broad impact on the development of IMCs-containing Pd catalysts.