Fashedemi, OOOzoemena, KI2014-05-222014-05-222013-12Fashedemi, O.O and Ozoemena, K.I. 2013. Enhanced methanol oxidation and oxygen reduction reactions on palladium-decorated FeCo@Fe/C core–shell nanocatalysts in alkaline medium. Physical Chemistry Chemical Physics, vol. 15(48), pp 20982-209911463-9076http://pubs.rsc.org/en/content/articlelanding/2013/cp/c3cp52601a/unauth#!divAbstracthttp://hdl.handle.net/10204/7428Copyright: 2013 Royal Society of Chemistry. This is an OA journal. The journal authorizes the publication of the information herewith contained.Palladium based nano-alloys are well known for their unique electrocatalytic properties. In this work, a palladium-decorated FeCo@Fe/C core-shell nanocatalyst has been prepared by a new method called microwave-induced top-down nanostructuring and decoration (MITNAD). This simple, yet efficient technique, resulted in the generation of sub-10 nm sized FeCo@Fe@Pd nanocatalysts (mainly 3-5 nm) from a micron-sized (0.21-1.5 µm) FeCo@Fe/C. The electrocatalytic activities of the core-shell nanocatalysts were explored for methanol oxidation reaction (MOR) and oxygen reduction reaction (ORR) in alkaline medium. A negative shift of 300 mV in the onset potential for MOR was observed, with a current thrice that of the Pd/C catalysts. A very low resistance to electron transfer (Rct) was observed while the ratio of forward-to-backward oxidation current (If/Ib) was doubled. The overpotential of ORR was significantly reduced with a positive shift of about 250 mV and twice the reduction current density was observed in comparison with Pd/C nanocatalysts with the same mass loading. The kinetic parameters (in terms of the Tafel slope (b) = -59.7 mV dec(-1) (Temkin isotherm) and high exchange current density (jo) = 1.26 × 10(-2) mA cm(-2)) provide insights into the favorable electrocatalytic performance of the catalysts in ORR in alkaline media. Importantly, the core-shell nanocatalyst exhibited excellent resistance to possible methanol cross-over during ORR, which shows excellent promise for application in direct alkaline alcohol fuel cells (DAAFCs).enNano-alloysElectrocatalytic propertiesPalladium (Pd)-based electrocatalystsDirect alkaline alcohol fuel cellsDAAFCsArticleFashedemi, O., & Ozoemena, K. (2013). Enhanced methanol oxidation and oxygen reduction reactions on palladium-decorated FeCo@Fe/C core–shell nanocatalysts in alkaline medium. http://hdl.handle.net/10204/7428Fashedemi, OO, and KI Ozoemena "Enhanced methanol oxidation and oxygen reduction reactions on palladium-decorated FeCo@Fe/C core–shell nanocatalysts in alkaline medium." (2013) http://hdl.handle.net/10204/7428Fashedemi O, Ozoemena K. Enhanced methanol oxidation and oxygen reduction reactions on palladium-decorated FeCo@Fe/C core–shell nanocatalysts in alkaline medium. 2013; http://hdl.handle.net/10204/7428.TY - Article AU - Fashedemi, OO AU - Ozoemena, KI AB - Palladium based nano-alloys are well known for their unique electrocatalytic properties. In this work, a palladium-decorated FeCo@Fe/C core-shell nanocatalyst has been prepared by a new method called microwave-induced top-down nanostructuring and decoration (MITNAD). This simple, yet efficient technique, resulted in the generation of sub-10 nm sized FeCo@Fe@Pd nanocatalysts (mainly 3-5 nm) from a micron-sized (0.21-1.5 µm) FeCo@Fe/C. The electrocatalytic activities of the core-shell nanocatalysts were explored for methanol oxidation reaction (MOR) and oxygen reduction reaction (ORR) in alkaline medium. A negative shift of 300 mV in the onset potential for MOR was observed, with a current thrice that of the Pd/C catalysts. A very low resistance to electron transfer (Rct) was observed while the ratio of forward-to-backward oxidation current (If/Ib) was doubled. The overpotential of ORR was significantly reduced with a positive shift of about 250 mV and twice the reduction current density was observed in comparison with Pd/C nanocatalysts with the same mass loading. The kinetic parameters (in terms of the Tafel slope (b) = -59.7 mV dec(-1) (Temkin isotherm) and high exchange current density (jo) = 1.26 × 10(-2) mA cm(-2)) provide insights into the favorable electrocatalytic performance of the catalysts in ORR in alkaline media. Importantly, the core-shell nanocatalyst exhibited excellent resistance to possible methanol cross-over during ORR, which shows excellent promise for application in direct alkaline alcohol fuel cells (DAAFCs). DA - 2013-12 DB - ResearchSpace DP - CSIR KW - Nano-alloys KW - Electrocatalytic properties KW - Palladium (Pd)-based electrocatalysts KW - Direct alkaline alcohol fuel cells KW - DAAFCs LK - https://researchspace.csir.co.za PY - 2013 SM - 1463-9076 T1 - Enhanced methanol oxidation and oxygen reduction reactions on palladium-decorated FeCo@Fe/C core–shell nanocatalysts in alkaline medium TI - Enhanced methanol oxidation and oxygen reduction reactions on palladium-decorated FeCo@Fe/C core–shell nanocatalysts in alkaline medium UR - http://hdl.handle.net/10204/7428 ER -