Controllable Design And Electrochemical Application Of Cu-based Single Atom/Alloy Functional Nanostructured Materials

With the progress of science and technology,the application field of electrochemistry is constantly expanding.Because of its environment-friendly,simple reaction and strong operability,it has a very broad application in the field of electrochemical reduction of carbon dioxide,electrochemical biosensor,electrolytic water hydrogen production and so on.It is of great significance to select appropriate electrode materials to promote the above reaction.However,in the current research,electrode materials in the application of poor electrochemical activity,low selectivity for products,poor electrochemical stability,easily oxidized,poor stability and other deficiencies,resulting in their practical application still has a huge challenge.Therefore,in this paper,a new type of Cu based monoatomic metal and alloy catalyst is constructed by the functional modification of Cu based nanostructured monatomic metal and alloying,and its application in the field of electrochemical glucose enzyme-free sensing and electrochemical CO₂reduction is explored.Specific work is as follows:1.Preparation of Ru₁/Cu@Cu₂O hollow nanotubes（NTs）and study on its electrochemical enzymatic glucose sensing properties.Firstly,a single atom Ru modified Cu@Cu₂O NTs was prepared by the substitution reaction of Cu nanowires with H₂Ru Cl₅,and then the existence of Ru single atoms was confirmed by using spherical aberration electron microscopy（AC-HAADF-STEM）and X-ray absorption fine structure spectroscopy（XAFS）.Prepared Ru₁/Cu@Cu₂O NTs materials exhibit high-performance electrochemical enzyme free glucose sensing performance,including high sensitivity(54.9μA·m M^-1/cm²),wide linear range（5μM～8 m M）,low detection limit（5μM.S/N>3）,high selectivity and good stability.Comparative experiments show that the incorporation of Ru monatoms greatly improves its electrocatalytic and electrochemically enzyme-free sensing performance for glucose molecules,which can be attributed to the excellent catalytic performance of Ru SACs and the electron interaction between Ru and Cu@Cu₂O NTs.This work demonstrates the potential application value of monoatomic catalysts in the field of electrochemical sensing.2.Controllable synthesis of Cu@Cu Sn Pb ternary core shell nanoparticles（NPS）and Performance Research on electrochemical CO₂reduction（CO₂RR）.Approximately 50 nm in diameter were prepared in the oil phase using a step wise reduction method Cu@Cu Sn Pb core-shell nanoparticles.Furthermore,Cu@Cu Sn Pb NPs exhibited the highest faradaic efficiency for CO,reaching 58.8%,which was nearly 10 times enhancement over Cu NPs.Meanwhile the competitive hydrogen evolution reaction faradaic efficiency was suppressed to below 15%,and good stability was achieved in 7 h.This illustrates Cu@Cu Sn Pb NPs showed good selectivity and good stability for CO₂reduction.Efficient catalytic performance,which can be ascribed to the unique core-shell structure as well as the modulation of the intermetallic interactions on the adsorption of intermediates.The ternary alloy nanomaterials developed in this study provide a new idea for the development of efficient CO₂RR catalysts.