【摘 要】
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Here,a class of metal-free nitrogen self-doped graphene(NG)catalyst for the oxygen reduction reaction(ORR)is in-vestigated.This catalyst(freeze-NG)is prepared from pyrolyzing marshmallow-like graphene
【机 构】
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School of Materials Science and Engineering,University of Shanghai for Science and Technology,Shangh
论文部分内容阅读
Here,a class of metal-free nitrogen self-doped graphene(NG)catalyst for the oxygen reduction reaction(ORR)is in-vestigated.This catalyst(freeze-NG)is prepared from pyrolyzing marshmallow-like graphene oxide(GO),which is obtained from freeze-drying,with a widely used nitrogen source,urea,at a high doped proportion.For comparison,a catalyst(hot-NG)prepared from the hot-dried thin film GO is also studied.The structure characteristics of these catalysts are measured by SEM,Raman,X-ray diffraction(XRD),BET and X-ray photoelectron spectroscopy(XPS).XPS shows that the Nat%is freeze-NG(1.54)> hot-NG(1.39),pyridinic-N in freeze-NG is higher than the hot-NG.The ORR electrocatalytic performances demonstrated by cyclic volta-mmograms and rotating ring disk electrode in 0.1M KOH shows that the nitrogen-doping and much defects of the NG sheets give the main contribution to the high ORR catalytic activity.Meanwhile,this facile way will also provide important insights into the rational optimization of catalytic activity of N-doped graphene for the ORR.
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