Prepartion Of Heteroatom Doped Carbon Nanomaterials And Research Of Their Electrochemical Oxygen Reduction

The development of clean,efficient new energy has attracted wide attention as the traditional fossil fuel combustion brought about issues which becomes increasingly prominent,such as environmental pollution,greenhouse effect and Rising sea level.As a new energy,fuel cell has the advantages of high energy,simple structure,small size,mild working conditions,fast start-up,clean and efficient.It has a very wide application in the fields of automobile power,aerospace and other fields.Today,the application of fuel cells which require platinum-based catalysts attached to the cathode to accelerate the Oxygen Reduction Reaction(ORR)is limited in industry due to its high cost,easy to decay and intolerance to methanol poisoning and other issues.In recent years,the research of oxygen reduction catalysts has focused on reducing platinum content in platinum-based catalysts and developing non-platinum-based catalysts.The heteroatom-doped carbon materials has been of concern because of their excellent oxygen reduction catalytic activity,high stability,and high methanol tolerance.Herein,We prepare a heteroatom doped carbon materials as ORR catalyst by hydrothermal method and pyrolysis method.The factors influencing the microstructure,chemical composition and electrochemical activity of the catalyst were systematically discussed.The main work of this paper is as follows:Typically,Coral-like polyaniline was synthesized by polymerization of aniline.Then,cobalt hydroxide was grown on the surface by hydrothermal method,Followed by pyrolysis.Cobalt/nitrogen codoped carbon-based ORR catalyst was obtained finally.The performance of the prepared catalyst was characterized by scanning electron microscopy(SEM),transmission electron microscopy(TEM),brunauer emmett teller(BET),X-ray photoelectron spectroscopy(XPS),cyclic voltammetry(CV)and linear scanning(LSV).The results reveal that the catalysts have high specific surface area and abundant micropore structure.the cobalt/nitrogen-codoped carbon microparticles catalyst prepared by pyrolysis at 900 °C has superior catalytic performance,a slightly active N-doped carbon catalyst becomes highly active with the incorporation of cobalt,When used as an ORR catalyst,its shows comparable halfwave and onset potentials to those of the Pt/C catalyst in alkaline electrolytes,favours a 4 electron transfer process toward ORR and it was displays superior durability,relatively free from methanol-crossover effects in alkaline electrolytes.In addition,the catalyst also has outstanding performance on the supercapacitor.The Prussian blue nanoparticles as templates,on whose surface polymerizating polypyrrole.In the following stage,iron/nitrogen codoped carbon material was obtained by calcination of polypyrrole coated with Prussian blue at high temperature.The obtained catalyst was characterized.It was found that the iron/nitrogen-codoped carbon nanoparticles catalyst prepared by pyrolysis at 900 °C has high efficiency for oxygen reduction catalysis,In the alkaline medium close to the efficient 4 electron transfer reaction,catalytic performance comparable to the current commercial Pt/C,and it has better stability and anti methanol interference performance than commercial Pt/C catalyst.Preparation of hollow nano-spherical polypyrrole and preparation of nitrogen-doped nano-carbon hollow spheres by high temperature pyrolysis,The performance of the prepared catalyst was tested by cyclic voltammetry(CV)and linear scanning(LSV).The results show that the prepared catalyst has good oxygen reduction catalytic performance.