Controllable synthesis of supported Cu–M (M =Pt, Pd, Ru, Rh) bimetal nanocatalysts and their catalytic performances

Based on the galvanic replacement reaction between Cu nanoparticles and noble metal ions, a simple and efficient strategy was developed for the preparation of supported Cu–M (M = Pt, Pd, Ru, Rh) bimetallic nanoparticles under intense ultrasonication irradiation at ambient environment. A series of Cu–M/TiO2 bimetal catalysts with controllable composition, metal particle size less than 2 nm and narrow size distribution were obtained, and characterized by transmission electron microscopy (TEM), high resolution transmission electron microscope (HRTEM) with scanning TEM (STEM) mode, energy-dispersive X-ray spectrometers (EDS), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), and ICP-AES analysis. It was demonstrated that most of the metal particles were present in the form of bimetallic state. The mechanism of this strategy was discussed. The resultant Cu–Pd/TiO2 was used to reduce nitrate at room temperature, and it exhibited extremely high activity.