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DOE OSTI · 1357036

Multimetallic Core/Interlayer/Shell Nanostructures as Advanced Electrocatalysts

Kang, Yijin·Snyder, Joshua·Chi, Miaofang·Li, Dongguo·More, Karren L.·Markovic, Nenad M.·Stamenkovic, Vojislav R.
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Abstract

The fine balance between activity and durability is crucial for the development of high performance electrocatalysts. The importance of atomic structure and compositional gradients is a guiding principle in exploiting the knowledge from well-defined materials in the design of novel electrocatalysts with a Ni core, Au interlayer and PtNi shell nanostructure (Ni@Au@PtNi). This multimetallic system is found to have the optimal balance of activity and durability due to the synergy between stabilizing effect of subsurface Au and modified electronic structure of surface Pt through interaction with subsurface Ni atoms. The electrocatalysts with Ni@Au@PtNi core-interlayer-shell structure exhibit high intrinsic and mass activities as well as superior durability for the oxygen reduction reaction with less than 10% activity loss after 10,000 potential cycles between 0.6 and 1.1 V vs. the reversible hydrogen electrode.

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activitydurabilityelectrocatalysisnanoparticlenanostructureoxygen reduction reaction

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Kang, Yijin, Snyder, Joshua, Chi, Miaofang, Li, Dongguo, More, Karren L., Markovic, Nenad M., Stamenkovic, Vojislav R.. 2014-11-12. Multimetallic Core/Interlayer/Shell Nanostructures as Advanced Electrocatalysts. https://doi.org/10.1021/nl5028205

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DOE OSTI2017

An overlooked nitrogen loss linked to anaerobic ammonium oxidation in estuarine sediments in China

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