PtRuNi/C novel nanostructures of platinum-ruthenium island-on-Ni/Ni(OH)2 nanoparticles for the selective hydrogenation of quinoline

Abstract Ni/C was successfully synthesized via hydrazine hydrate reduction at room temperature (RT). Pt/C, Ru/C and PtRu/C were prepared via an impregnation method. PtNi/C, RuNi/C and PtRuNi/C were synthesized via a chemical replacement method. The characterization results revealed that PtRuNi nanoparticles (NPs) were highly and uniformly dispersed on carbon black in PtRuNi/C. PtRuNi/C showed a novel nanostructure in which PtRu islands (PtRu nanoclusters or PtRu binary atoms) covered Ni/Ni(OH)2 NPs. PtRuNi/C trimetallic nanomaterial exhibited an optimum catalytic performance (turnover frequency (TOF) = 211.4 h−1 and selectivity for the production of 1,2,3,4-tetrahydroquinoline (py-THQ) > 99%) in the selective hydrogenation of quinoline at 60 °C under 5.0 MPa H2. The catalytic properties of PtRuNi/C were significantly improved as compared to bimetallic (PtNi/C, RuNi/C and PtRu/C) and monometallic (Ni/C, Pt/C and Ru/C) nanomaterials due to its unique nanostructure, with an observed nano-synergy effect among Pt-, Ru- and Ni-related species.