Preparation Of Palladium-based Bimetallic Nanocatalysts And Their (photo)electrocatalytic Propertie

As a member of the noble metal family,palladium(Pd)nanomaterials play an important role in the fields of catalysis,sensing,energy science and organic synthesis.Compared with single-element noble metal nanocrystals,Pd-based bimetallic nanocrystals formed by introducing another metal element have developed rapidly by virtue of their unique physical and chemical properties.Catalysis plays an important role in modern chemistry,and ideal electrocatalysts should not only have high catalytic activity,but also have good structural stability.In recent years,surface defect-rich nanocatalysts and new plasmonic nanocatalysts are emerging,both of which certainly improve the activity and stability of catalysts to a certain extent.In this work,additional metal ions were introduced in the seed-mediated growth of Pd nanocrystals to form Pd-based bimetallic nanocrystals.These discoveries is of vital importance for the rational design of the morphology and structure of noble metal nanomaterials and provide theoretical guidance for the practical application of noble metal nanomaterials.Our main research results are as follows:First,the synthesis of surface-rich Pd-Cu nanocubes by a Cu(II)-assisted seed-mediated method was demonstrated and a new method for constructing surface defects was successfully obtained.Cu(II)enables the rapid growth of Pd atoms selectively along the {110} and {111} directions of cubic Pd,thereby promoting the formation of stepped structures on the surface of nanomaterials.The electro-oxidation reaction results of ethanol confirmed the excellent catalytic activity and stability of the surface-rich palladium-copper nanocubes.Second,a nanocatalyst composed of Au-framed Pd nanocubes was rationally designed and synthesized by an Ag(I)-assisted seed-mediated growth method.In the synthesis,the incorporation of Ag(I)suppressed the reduction of gold on the {100}surfaces of cubic Pd seeds and resulted in the formation of Au nanoframes on the Pd nanocubes.Meanwhile,the Au-framed Pd nanocubes exhibit excellent plasmon resonance properties.This unique nanostructure exhibits high catalytic activity and stability for the plasmon-enhanced electrocatalytic oxidation of ethanol by combining the excellent electrocatalytic properties of Pd with the outstanding plasmonic properties of Au.