CONICET | Buscador de Institutos y Recursos Humanos

Pd nanoparticles of 16 nm were synthesized in graphite oxide (GO) via cation exchange. The synthesis procedure involved immobilization of the precursor Pd(NH3)4(NO3)2 in GO, followed by reduction in flowing H2. The resulting low-loaded PdGO material was characterized by X-ray diffraction (XRD), infrared (IR) spectroscopy and transmission electron microscopy (TEM). Structural characterization revealed that intercalation of the precursor took place in GO and the reduced Pd nanoparticles were situated both on the external surface and in the interlamellar space of the GO lamellae. The catalytic behaviour of PdGO was investigated in the liquid-phase hydrogenations of 3-hexyne and 4-octyne under standard conditions. For both reactants, marked turnover frequencies (1836 s_1) and pronounced (Z)-alkene stereoselectivities (9398.4%) were obtained, indicating that PdGO was a highly active and stereoselective catalyst. For the stereoselective hydrogenation of 3-hexyne, PdGO exhibited an outstanding catalytic performance: at reactant:Pd (S:Pd) ratios 6 5000, complete conversions were achieved in 815 min and the (Z)-alkene stereoselectivities exceeded 98%.