In:
ECS Meeting Abstracts, The Electrochemical Society, Vol. MA2017-02, No. 45 ( 2017-09-01), p. 1998-1998
Abstract:
It was recently reported that thin films of nickel-gallium, prepared simply by drop-casting aqueous salt solutions onto graphite plates, were active for carbon dioxide reduction in aqueous carbonate electrolytes acidified to pH 6.8 with 1 atm CO 2 . The Ni-Ga thin films produce mixtures of methane, ethylene and ethane at potentials as anodic as -0.48V vs RHE, representing some of the lowest onset potentials for C2-product formation reported to date. While polycrystalline Cu also produces CH 4 and C 2 H 4 , the onset potential for these products on Ni-Ga films is several hundred millivolts more positive. However, the current densities on Ni-Ga are ~ 3 orders of magnitude lower than Cu. One strategy to improve the current densities is the use of nanostructured Ni-Ga catalysts. Thus, we present a novel synthesis of Ni-Ga nanoparticles for the purpose of probing their carbon dioxide reduction behavior. Micrometer sized clusters of Ni 3 Ga nanoparticles (~8-13 nm in diameter) were synthesized from the reflux of Ni(COD) 2 and Ga(acac) 3 salts in 1-octadecene solvent at 310°C (COD = cyclooctadiene, acac = acetylacetonate). The nanoparticles were supported on carbon black (Vulcan XC-72) and fabricated onto a glassy carbon electrode with ionomer solution. Interestingly, in aqueous K 2 SO 4 electrolyte saturated with 1 atm CO2 (pH 4.38), the Ni-Ga nanoparticles reduced CO 2 to formic acid with Faradaic efficiencies as high as 36% at -0.92 V vs RHE. This contrasting activity to Ni-Ga thin films is discussed with an emphasis on the effect of composition, surface structure, and support of the catalyst. Figure 1
Type of Medium:
Online Resource
ISSN:
2151-2043
DOI:
10.1149/MA2017-02/45/1998
Language:
Unknown
Publisher:
The Electrochemical Society
Publication Date:
2017
detail.hit.zdb_id:
2438749-6
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