▎ 摘　　要

In this work, monodispersed core-shell AuPt@Au nanocrystals supported on reduced graphene oxide (AuPt@Au NCs/rGO) were fabricated by a one-step wet-chemical approach using melamine as a structure-director and stabilizing agent. Transmission electron microscopy (TEM), high-angle annular dark-field scanning TEM (HAADF-STEM), X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS) were employed to examine their structure and morphology. The as-synthesized nanocomposites displayed better catalytic activity for p-nitrophenol reduction and improved reusability as compared with monometallic Au/rGO, Pt/rGO and commercial Pt/C catalysts.