We are living in era, when society is giving more and more attention to sustainable development and there is currently a lot of research focused on the development of fuel cells. The major disadvantage of these is the stability and activity of ORR catalysts. Graphene and its modifications have recently been highly researched materials due to the remarkable properties that can be used in various fields. Nitrogen doped graphene has a great potential for use in fuel cells mostly because of its electrocatalytic properties.
I prepared the material from natural graphite, synthetic graphite, C-grade MWCNTs and X-long MWCNTs. First step was oxidation of those starting materials with Hummer's method, which has proven to be a crucial step, since the degree of oxidation affects the possibility of doping the material with nitrogen. Oxidation was followed by doping with three different processes. Prepared material was then characterized with scanning electron microscope (SEM), elemental analysis (CHN), Raman spectroscopy, thermogravimetric measurements coupled with mass spectroscopy, X-ray photoelectronic spectroscopy (XPS), energy dispersive X-ray spectroscopy (EDS) and BET analysis. The most promising way of preparing nitrogen doped graphene as catalyst for ORR and as membrane in DEFC based on findings in this research is material prepared from graphite with thermal annealing in ammonia.
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