Study On Electrocatalytic Activity Of Supported Metal Nanocatalysts

Electrochemical catalysts are the core of electrocatalytic reactions.Highly efficient electrocatalysts can effectively reduce the activation energy of electrocatalytic reactions and increase their catalytic activity.The optimized design of electrocatalysts and the design of efficient and low-cost electrochemical catalysts under mild conditions have always been the focus of research in the field of electrocatalysis.For a long time,researchers have devoted themselves to selecting suitable materials to design efficient and feasible electrocatalysts.When the metal nanoparticles are loaded on the support,the interaction between the metal nanoparticles and the support will affect the catalytic activity of the metal nanoparticles,and its chemical properties will be changed.This phenomenon is called the"support effect".The carrier effect has a great influence on the catalytic activity of the catalyst.In this paper,based on the effect of the carrier effect on the supported metal nanocatalyst and the effect of the charge transfer between different carriers and metal nanoparticles on its catalytic activity,the two aspects are studied as follows:?1?Study on the catalytic properties of Pd nanoparticles by Mo S₂ supportSemiconductor materials are often used as supports for supporting metal catalysts,which can affect the electronic state density of metal catalysts by interfacial metal-support interaction?"EMSI"?.Here,we proposed to use the semiconductor Mo S₂to regulate the Pd nanoparticle energy level by EMSI?the composite material is named Pd-Mo S₂?,and further used the hydrogen evolution reaction?HER?as the model reaction system to study the effect of the"support effect"of Mo S₂ on the catalytic activity of Pd.The experimental results showed that Pd-Mo S₂ exhibits excellent HER catalytic activity compared to ce-Mo S₂ and commercial Pd/C,indicating that the Mo S₂ support can effectively regulate the energy level of the catalyst.?2?Energy level regulation of Pd nanoparticles and its electrocatalytic oxidation performance of formic acidThis part uses the"support effect"to regulate the catalytic activity of the Pd nanoparticle catalyst's formic acid oxidation reaction.We designed four different oxide-loaded Pd nanoparticle catalysts to catalyze the oxidation of formic acid.The electron transfer between the four catalyst supports and Pd nanoparticles was compared by XPS and CO stripping voltammetry,and their formic acid oxidation activity was combined.We found that the amount of electron transfer between the Pd nanoparticles and the carrier is positively correlated with the catalytic activity of the formic acid,that is,when the surface electron density of the Pd nanoparticles is lower,the catalytic activity of formic acid oxidation is higher.This proved the effect of the support effect on the catalytic activity of the catalyst from the electronic level.