Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
6471273 | Electrochimica Acta | 2017 | 11 Pages |
â¢Hollow nanocubes of sodium nickel fluoride on MWCNTs are used for urea oxidation.â¢SNF-MWCNT catalysts showed much better catalytic activity than commercial Ni-C.â¢SNF-MWCNT-5 ml IL yields a maximum current density of 3.12 A cmâ2 mgâ1.â¢Direct urea/air unit fuel cell showed a promising performance at very low loading of SNF.â¢Ni3+ rich surface and electronic effect between Ni and F promoted urea oxidation.
Hollow nanocubes of sodium nickel fluoride deposited on multiwall carbon nanotubes (SNF-MWCNT) have been synthesized by a facile microwave assisted process using in situ templated mechanism. Ionic liquid (IL) played an important role in synthesizing the catalysts. Physicochemical properties of the catalysts were characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), and X-ray photoelectron spectroscopy (XPS). The catalysts were analyzed for urea electrooxidation using cyclic voltammetry (CV), chronoamperometry (CA), and electrochemical impedance spectroscopy (EIS) tests. The SNF-MWCNT electrocatalyst exhibited a very high current density of 3.12Â AÂ cmâ2Â mgâ1 at 20Â mVÂ sâ1 in 0.33Â M urea and 5Â M KOH solution aided by their Ni3+ rich surfaces, a porous and hollow structure and a favorable electronic effect of fluorine. The catalytic activity of SNF-MWCNT for urea oxidation was found superior than the commercially available Ni-C catalyst. The direct urea/air unit fuel cell showed a very promising performance by using SNF-MWCNT-5Â mL IL as anode catalyst with a low amount of loading.
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