Study On Transition Metal Doped MoS₂ Loaded On Carbon Felt For Water Splitting And Zinc-Air Battery

Water splitting and rechargeable zinc-air batteries are currently the important means to address energy shortages and environmental pollution issues.Including of the hydrogen evolution reaction（HER）and oxygen evolution reaction（OER）involved in water splitting devices,and the oxygen evolution reaction（OER）and oxygen reduction reaction（ORR）occurring on the cathode of zinc-air batteries,high-performance multifunctional catalysts are required to accelerate the reaction rate and improve energy conversion efficiency.In this thesis,transition metal doped MoS₂coated carbon felt composite electrodes were designed and prepared,and their multifunctional catalytic mechanism was analyzed to understand the properties of their applications in water splitting and rechargeable zinc-air batteries.Firstly,transition metal doped MoS₂catalysts loaded on conductive carbon felt were prepared through a simple one-step hydrothermal method.The experimental results show that doped MoS₂loaded on carbon felt,especially Fe doped MoS₂,shows excellent multifunctional electrocatalytic activity and stability,which can be attributed to the semiconductor characteristics of the active layer and the appropriate surface coverage ratio to expose more active site.Electrochemical analysis has confirmed that defect regulation can be achieved by doping metal ions,which changes the surface properties,band structure,and ion adsorption and desorption properties of MoS₂layer.High-performance multifunctional catalytic properties of composite electrodes could be attributed to effectively improves the ion transport and electron transport ability between electrodes and electrolytes through collaborating with carbon felt,and thus enhances the performance of composite electrodes for water splitting and zinc-air batteries.Secondly,two methods,nitric acid acidification and carbon quantum dot modification,were used to treat the surface of carbon felt in order to investigate the effect of conductive substrate surface properties on the multifunctional electrocatalytic performance of composite electrodes.The experimental results show that the surface morphology,electronic structure,conductivity and defect density of the loaded active material can be modulated by changing the composition of carbon,nitrogen and oxygen elements on the surface of the carbon felt.Through changing the composition and proportion of the surface elements,the multifunctional catalytic properties of the composite electrode can be effectively controlled,as well as the performance of water splitting and zinc-air batteries based on composite electrodes.In summary,we provide research ideas for the development of high-performance multifunctional catalysts and their applications in the fields of water splitting and zinc-air batteries.