Synthesis And Properties Of Electrocatalysts Based On Metal Organic Framework Nanocomposite Structures

Rechargeable type zinc air battery has the material cost is low,the specific energy,high density,high safety performance and environment friendly advantages,it is the most development potential of a new generation of energy technology,andit caused the researchers pay close attention to.Catalytic material is the core component of rechargeable zinc air battery type,its catalytic activity and stability has a great influence to energy conversion efficiency and the charging and discharging cycle stability of metal air batteries.Catalytic materials is therefore decided to rechargeable zinc air battery performance of key materials.The ideal rechargeable zinc-air cell catalytic material should be a bifunctional catalytic material with both oxygen reduction?ORR?reaction and oxygen precipitation?OER?reaction activity.Therefore,the development of efficient and stable bifunctional catalytic materials has become the key to the development of rechargeable zinc-air batteries.Based on the above design ideas of catalytic materials,Based on the key scientific and technological problems faced by the rechargeable zinc-air battery,a novel bifunctional catalytic material with novel microstructure and structure was synthesized under relatively mild conditions.The effects of microstructure characteristics of catalytic materials on catalytic activity and stability are also studied,which provides experimental basis and theoretical reference for the performance optimization of bifunctional catalytic materials.This article is composed of the following parts:Firstly,this section summarizes the development history of zinc-air battery,emphasizes its necessary path as a new energy development,briefly describes the basic principle of charging and discharging of the cathode part of zinc hollow battery,and conducts experimental research on the purpose of low cost and high performance as a substitutable platinum-base catalyst.Secondly,Ag₂S nanorods with a diameter of about 50 nm were synthesized from 200 to250 nm prepared by means of chemical bath.After that,the Ag2S/ZIF-8 composite materials on the surface of ZIF-8 or inside were prepared.The catalyst was characterized by HR-TEM,FESEM,Mapping,EDX,BET,XRD,etc,The results showed that the Ag2S nanorods were successfully embedded in ZIF-8 surface or coated in ZIF-8,and electrochemical tests showed that the catalyst had a certain bifunctional catalytic activity and stability.Thirdly,Ag₂S nanorods with a diameter of about 50 nm were synthesized from 200 to250 nm,and ZIF-67 coated Ag₂S composite materials were prepared by chemical bath.The catalyst was characterized by HR-TEM,FESEM,Mapping,EDX,BET,XRD,etc.The results showed that the Ag₂S nanorods were successfully coated in ZIF-67,and the electrochemical test showed that the catalyst had excellent bifunctional catalytic activity and stability.Fourthly,The Ag₂S nanorods have synthesized,which are 200²50 nm long and have a base diameter of about 50 nm.the first,Ag₂S/ZIF-8 composite materials were prepared according to the synthesis method of chapter 3.the second,a layer of ZIF-67 material was coated on the surface of Ag₂S/ZIF-8 composite material by means of solvent heating.The catalyst was characterized by HR-TEM,FESEM,Mapping,EDX,BET,XRD,etc.The results showed that the surface of Ag2S/ZIF-8 composite was successfully coated with ZIF-67material,and electrochemical characterization showed that the catalyst had the best excellent catalytic activity and stability.In conclusion,Ag₂S nanorods were synthesized,and a composite catalyst with different ZIF structures was synthesized on this basis,which effectively improved the performance of the cathode catalyst of Zinc air batteries.Through the scientific characterization method,the structure morphology of the composite catalyst and the effect of synergistic catalytic effect on the activity of the catalyst were studied systematically.