Abstract: Uniform and well-defined Ir-Pd bimetallic trioctahedral nanocrystals with an average size of 50 nm are synthesized by using Ir(acac)3 and H2PdCl4 as precursors,tetraethylene glycol (TEG) as solvent and reduction agent,ascorbic acid (AA) as a co-reduction agent,polyvinylpyrrolidone (PVP) as a stabilizer,KI as a shape-controlled agent under microwave irradiation for 120 s.In the reaction system,the optimum molar ratio of Ir(acac)3∶H2PdCl4∶AA∶KI∶PVP is 1∶3∶2∶10∶15.The products are characterized by transmission electron microscopy (TEM),scanning electron microscope (SEM),X-ray diffraction (XRD) and X-ray photoelectron spectrometry (XPS).The electrocatalytic activity of the as-prepared Ir-Pd bimetallic trioctahedral nanocrystals for electro-oxidation of formic acid is around 2.5 times that of the commercial Pd black.
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