عنوان مجله
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Materials Research Express
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چکیده
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In this work, we report simultaneous electrochemical exfoliation of graphite powder using SDS,
anionic surfactant salts, and cyclic potential to prepare graphene on carbon paper. Then, Nickel is
electro-reduced into graphene nanosheets on carbon paper and also on the bare carbon paper to
use in alkaline media for hydrogen evolution reaction (HER) and oxygen reduction reaction (ORR).
Afterward, graphene and Ni-graphene are characterized using scanning electron microscopy, atomic
force microscopy (AFM) and electrochemical technique. SEM images show the Cauliflower structure
of Ni in the absence of graphene and nanoparticle shapeless in the presence of smooth graphene. The
electrochemical results show an excellent catalytic activity of Ni-graphene/ carbon paper with an over
potential of 90 mV (Versus Ag/AgCl), which is lower than the literature value for Ni in alkaline
electrolyte for HER(120 mV dec−1). The effect of graphene support on the electrochemical impedance
spectroscopy response, activation energy and HER activity of the samples are investigated carefully.
Finally, we prepare a novel gas diffusion electrode by using Ni pasted on carbon paper for the ORR in
fuel cells and compared it with standard Pt/C catalysts using linear sweep voltammetry
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