TY - JOUR
T1 - Electrocatalytic activity of Ni-doped nanoporous carbons in the electrooxidation of propargyl alcohol
AU - García-Cruz, Leticia
AU - Sáez, Alfonso
AU - Ania, Conchi O.
AU - Solla-Gullón, José
AU - Thiemann, Thies
AU - Iniesta, Jesús
AU - Montiel, Vicente
N1 - Funding Information:
This work was funded by the Spanish MINECO (Grants CTQ2010-20347 , CTM2011-23378 ).
PY - 2014/7
Y1 - 2014/7
N2 - Herein, we explore the immobilization of nickel on various carbon supports and their application as electrocatalysts for the oxidation of propargyl alcohol in alkaline medium. In comparison with massive and nanoparticulated nickel electrode systems, Ni-doped nanoporous carbons provided similar propargyl alcohol conversions for very low metallic contents. Nanoparticulated Ni on various carbon supports gave rise to the highest electrocatalytic activity in terms of product selectivity, with a clear dependence on Ni content. The results point to the importance of controlling the dispersion of the Ni phase within the carbon matrix for a full exploitation of the electroactive area of the metal. Additionally, a change in the mechanism of the propargyl alcohol electrooxidation was noted, which seems to be related to the physicochemical properties of the carbon support as well. Thus, the stereoselectivity of the electrooxidative reaction can be controlled by the active nickel content immobilized on the anode, with a preferential oxidation to (Z)-3-(2-propynoxy)- 2-propenoic acid with high Ni-loading, and to propiolic acid with low loading of active Ni sites. Moreover, the formation of (E)-3-(2-propynoxy)-2-propenoic acid was discriminatory irrespective of the experimental conditions and Ni loadings on the carbon matrixes.
AB - Herein, we explore the immobilization of nickel on various carbon supports and their application as electrocatalysts for the oxidation of propargyl alcohol in alkaline medium. In comparison with massive and nanoparticulated nickel electrode systems, Ni-doped nanoporous carbons provided similar propargyl alcohol conversions for very low metallic contents. Nanoparticulated Ni on various carbon supports gave rise to the highest electrocatalytic activity in terms of product selectivity, with a clear dependence on Ni content. The results point to the importance of controlling the dispersion of the Ni phase within the carbon matrix for a full exploitation of the electroactive area of the metal. Additionally, a change in the mechanism of the propargyl alcohol electrooxidation was noted, which seems to be related to the physicochemical properties of the carbon support as well. Thus, the stereoselectivity of the electrooxidative reaction can be controlled by the active nickel content immobilized on the anode, with a preferential oxidation to (Z)-3-(2-propynoxy)- 2-propenoic acid with high Ni-loading, and to propiolic acid with low loading of active Ni sites. Moreover, the formation of (E)-3-(2-propynoxy)-2-propenoic acid was discriminatory irrespective of the experimental conditions and Ni loadings on the carbon matrixes.
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U2 - 10.1016/j.carbon.2014.02.066
DO - 10.1016/j.carbon.2014.02.066
M3 - Article
AN - SCOPUS:84897444008
SN - 0008-6223
VL - 73
SP - 291
EP - 302
JO - Carbon
JF - Carbon
ER -