Study On Preparation And Performance Of Efficient Electrocatalysts Based On MOFs

With the increasing demand of energy and the serve climate change caused by the burning of fossil fuels,it has aroused great interests in the development of renewable and clean energy.Especially important are the energy storage and conversion technologies,such as water splitting and fuel cells.The use of high-performance catalysts is regarded as the effective way to reduce the energy of required for the kinetics of chemical reactions in electrolytic water and fuel cell.Metal Organic Frameworks,as a new kind of ordered porous crystalline material,have the advantages of high porosity,large specific surface area,unsaturated coordination sites and flexible modification and clippable,which make it to become one of the potential candidate material for the preparation of electrocatalysts.In this thesis,based on rational choice and synthesis of MOFs as precursor,efficient electrocatalytic materials were obtained through the heating treatment.Then,structural morphology and electrochemical properties of these electrocatalytic materials were carried out.The main research contents are listed as follows:(1)Preparation of Ni@NC electrocatalytic materials and study on their hydrogen evolution properties.The Ni@NC electrocatalyst was obtained by carbonation of Ni-MOF precursors.The CV were used to deposit Pt nanoparticles on Ni@NC.The test results showed that the hydrogen evolution performance of the material was comparable to that of commercial Pt/C(20%)after 3500 CV cycles and had good stability was realized as well,which provides a new idea for the design efficient Pt-based electrocatalysts.(2)Preparation of Co@NC electrocatalysts materials and study on their oxygen reduction performance.The Co@NC electrocatalytic materials were prepared by directly carbonization of Co-MOF precursor.Then the activity for oxygen reduction,long-time stability and methanol resistance were tested.The results showed that the incorporation of cobalt element can significantly improve the oxygen reduction performance,which provides a reference for the synthesis of carbon-based non-noble metal nanocatalysts in the future.(3)Preparation of Co@NC-P electrocatalysts and study on their oxygen reduction performance.The Co@NC-P electrocatalysts were achieved by carbonization of a mixture of Co-MOF and triphenylphosphine and the oxygen reduction activities were measured with different mass ratios.The results showed that when the mass ratio of Co-MOF to triphenylphosphine was 3:1,the obtained Co@NC-P(3-1)exhibited the best oxygen reduction performance.