Exfoliated MoS2 supported Au-Pd bimetallic nanoparticles with core-shell structures and superior peroxidase-like activities

Au-Pd bimetallic nanoparticles (NPs) with core-shell structures have been successfully anchored on chemical exfoliated MoS2 (Au-Pd/MoS2) through a facile co-reduction method at room temperature. The Au-Pd/MoS2 hybrids were characterized by X-ray diffraction (XRD), scanning electronic microscopy (SEM), high-resolution transmission electron microscopy (HRTEM), energy dispersive X-ray spectroscopy (EDX) and X-ray photoelectron spectroscopy (XPS). The pristine MoS2 nanosheets exhibit some peroxidase-like activity for the oxidation of 3,3,5,5-tetramethylbenzidine (TMB), and their catalytic activity is significantly enhanced by the deposition of Au-Pd NPs. A systematic study revealed that Au-Pd NPs with a mass ratio of 1 : 2 on MoS2 (Au1.0Pd2.0/MoS2) showed the highest catalytic activity compared with other counterparts. This excellent performance of the Au1.0Pd2.0/MoS2 hybrids should be ascribed to not only the intrinsic catalytic activity of MoS2, but also the complicated metal-metal and metal-support interactions.