Abstract
Transition metal carbide shows excellent performance in selective hydrogenation of acetylene, however, the carburization of Pd-based intermetallic compounds remains infeasible. Here we report the successful synthesis of an unprecedented Pd(3)ZnC(x) intermetallic carbide, via co-infiltration of zinc and carbon in one-step carburization by syngas. Utilizing state-of-the-art in situ characterizations and theoretical calculation, we unveil the dynamic evolution of Pd(3)ZnC(x) during carburization, forming a Pd(3)Zn like cubic phase carbide structure. A unique transitional state (Pd(t)) with low content of Zn/C co-infiltration is clearly identified facilitating phase transition and sustain incorporation of carbon and zinc at elevated temperatures. The Pd(3)ZnC(x) carbide shows by far the best catalytic performance in the selective hydrogenation of acetylene with a high selectivity (>90%) even at a high H(2)/C(2)H(2) ratio. Our results therefore provide a co-infiltration strategy and dynamic insights for the one-step synthesis of Pd based intermetallic carbides, towards high-performance intermetallic compound for selective hydrogenation of acetylene.