Ionic Liquid-based Synthesis Of Ultrafine Metal Nanomaterials And Study On Its Electrocatalytic Performance

Metal nanoparticles have been characterized by their unique atomic and electronic structures and excellent electrocatalytic properties.Their synthesis and application have always been hot research topics in the field of materials science.It is a very green method to use ionic liquids?ILs?with low vapor pressure,high solubility,and specific structural order of ILs as a protective agent in metal synthesis to prepare ultrafine nanoparticles.Nanocatalysts prepared using the advantages of both ionic liquids and metal nanomaterials are used to electrochemically reduce CO₂ and oxidized ethanol to make a little contribution to environmental purification and energy storage.In this paper,based on previous researches,the work was carried out using amino-functionalized ionic liquid?1-aminoethyl-3-methylimidazole tetrafluoroborate?to protect ultrafine metal nanoparticles and obtain a gold-palladium core-shell?Au@Pd?structure of ultra-fine nanoparticles and ultra-fine copper-gold?CuAu?alloy nanoparticles,and conduct electrochemical performance studies;using transmission electron microscopy?TEM?,high-resolution transmission electron microscopy?HTEM?,cold field emission double spherical aberration Calibrate transmission electron microscopy?STEM?to characterize the morphology of the sample,using ultraviolet-visible absorption spectroscopy?UV-vis?,X-ray photoelectron spectrometer?XPS?,inductively coupled plasma atomic emission spectroscopy?ICP?and other characterization methods The physical and structural properties of the nanoparticles are analyzed and understood,and the electrocatalytic performance of the synthesized catalyst is tested using an electrochemical workstation and a gas chromatograph?GC?.This paper mainly contains the following research contents:?1?Using the functional ionic liquid 1-aminoethyl-3-methylimidazole tetrafluoroborate as a protective agent for metal synthesis,a gold-palladium core-shell?Au@Pd?structure was synthesized using a seed-mediated growth method Ultrafine nanoparticles,the obtained metal nanoparticles are characterized by TEM,HTEM,STEM,etc.;the metal particles with good morphology are loaded on carbon black,and the catalysts are treated with UV-vis,XRD,XPS Analysis of structure and physicochemical properties.The characterization results show that the ultra-fine Au@Pd core-shell particles have a particle size of about 2-4 nm and good morphology.Quantitative analysis and electrochemical application research on metal particles with different molar ratios of metal components using ICP-MS and electrochemical workstations.Au@Pd core-shell nanoparticles are used for electrochemical ethanol oxidation performance studies,and commercial Pd phase In comparison,Au@Pd core-shell nanoparticles are 11 times more oxidized than ethanol,and have good stability.?2?Using functional ionic liquid 1-aminoethyl-3-methylimidazole tetrafluoroborate as a protective agent for metal synthesis,ultrafine copper gold?CuAu?alloy nanoparticles were synthesized by one-pot method.The metal nanoparticles adopt a series of characterization methods,including TEM,HTEM,to observe the morphology of the sample;the metal particles with good morphology are loaded on carbon black,and the structure and catalyst of the catalyst are UV-vis,XRD,XPS Physical and chemical properties are analyzed.The characterization results show that the particle size of the prepared ultrafine CuAu alloy is around 2-4 nm,and the morphology is good.Then use electrochemical workstation,GC,ICP-MS to conduct quantitative analysis and electrochemical application of metal particles with different molar ratios of metal components,and use copper-gold alloy nanoparticles for the performance of electrochemical reduction of CO₂,and found that CO₂ The Faraday efficiency of the reduced CO increases with increasing Au content.When the molar ratio of Cu/Au is 1/9,the CO Faraday efficiency is the highest,about 75.8%.