An alkynyl-protected Ag13−xCu6+x nanocluster for catalytic hydrogenation

A novel alkynyl-stabilized silver-copper alloy nanocluster with the composition of [Ag_13-xCu_6+x(^tBuC₆H₄CC)₁₄(PPh₃)₆](SbF₆)₃ was prepared by the (PPh₃)₂CuBH₄-mediated reduction approach. The nanocluster features a centred disordered-octahedral Ag₇Cu₆ kernel, which is protected by hybrid alkynyl and triphenylphosphine ligands. Structural comparison of this two-electron nanocluster with other alkynyl-capped Ag/Cu ones suggested that the structure of alkynyl ligands played an important role in dictating the structures of the resulting nanoclusters. The title cluster showed high performance in the catalytic hydrogenation of 4-nitrophenol, indicative of the bright future of cluster-based catalysts.