The Application Of Heteroatom Doped Carbon Based Materials In Fuel Cells

Exploring low price,high-performance the oxygen reduction reaction(ORR)electrocatalyts to instead of platinum(Pt)-based fuel cell cathode catalyst,is of great importance for solving the problems of high cost,low activity and poor stability of Pt-based catalyst which hinder the commercialization of fuel cell process.Due to their good electrical conductivity,outstanding chemical and thermodynamic stability,controllable structure and large surface area,carbon-based materials are widely applied in adsorption,catalysis and energy storage.Among them,heteroatom-doped carbon-based materials represent one of the most promising electrocatalysts for ORR to replace Pt-based catalyst,due to their advantages of low cost,high activity and excellent durability.Heteroatom-doped carbon-based materials has become a hot research,is widely researched in the fields of catalysis and energy storage in recent years.However,there are some problems in this kind of material at present,such as low catalytic activity(especially in acid system),unclear catalytic mechanism and the active center.In order to solve these problems,we have done the following work:(1)Herein,we report a template-free,economic and environment-friendly strategy for scalable synthesis of N-doped hierarchical porous carbon nanosheets(N-HPCNSs)with biomass water lettuces as carbon precursor.The N-HPCNSs were demonstrated to possess three dimensional(3D)hierarchical porous structures with a high surface area and uniform N-doping.Systematic electrochemical study revealed that the N-HPCNSs not only hold numerous active sites but also manifest high intrinsic activity for each of the active sites toward ORR in pH-universal electrolyte of alkali,acid and neutral.With the N-HPCNSs as cathode electrocatalyst,three types of home-made fuel cells were set up that run in alkaline,acidic and neutral medium,i.e.,Zn-air alkaline fuel cells(ZABs),microbial fuel cell(MFCs),and direct methanol fuel cell(DMFCs),respectively,further demonstrating its potential to replace the high-cost Pt-based electrocatalysts for practical applications.(2)We report a facile method for preparing a 3D porous nanoarchitecture with Co nanoparticles inlayed in nitrogen-doped porous carbon(Co/N-MCs).The hybrid nanomaterial exhibits excellent electrocatalytic activity for the oxygen reduction(ORR)and glucose oxidation reaction(GOR)due to the synergistic contribution of the Co nanoparticles and nitrogen doping in the porous carbon base.Benefitting from the outstanding ORR and GOR electrocatalytic activity of the hybrids,a home-made glucose fuel cell(GFC)was set up using the Co/N-MCs as the both anode and cathode material,delivering a considerable power density with decent stability.