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Engineering Commons

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Electrical and Computer Engineering

Andrew C. Hillier

Selected Works

2003

Articles 1 - 2 of 2

Full-Text Articles in Engineering

Measuring Electrocatalytic Activity On A Local Scale With Scanning Differential Electrochemical Mass Spectrometry, K. Jambunathan, Andrew C. Hillier Dec 2002

Measuring Electrocatalytic Activity On A Local Scale With Scanning Differential Electrochemical Mass Spectrometry, K. Jambunathan, Andrew C. Hillier

Andrew C. Hillier

This paper describes a new technique entitled scanning differential electrochemical mass spectrometry ~SDEMS! that combines a quadrupole mass spectrometer with a membrane-covered capillary inlet and a high resolution positioning system that is designed to perform spatial mapping in solution near an electrode interface. Potential applications of this technique include the local characterization of anode catalysts for fuel cells as well as a range of analytical measurements and combinatorial screening studies. The capabilities of this technique are demonstrated by monitoring product evolution in several model electrocatalytic reactions, including the hydrogen evolution reaction, carbon monoxide oxidation, and the direct oxidation of methanol …


Screening The Reactivity Of Ptxruy And Ptxruymoz Catalysts Toward The Hydrogen Oxidation Reaction With The Scanning Electrochemical Microscope, S. Jayaraman, Andrew C. Hillier Dec 2002

Screening The Reactivity Of Ptxruy And Ptxruymoz Catalysts Toward The Hydrogen Oxidation Reaction With The Scanning Electrochemical Microscope, S. Jayaraman, Andrew C. Hillier

Andrew C. Hillier

We report an application of the scanning electrochemical microscope that exploits its ability to spatially map the kinetics of heterogeneous electron-transfer reactions in order to perform screening measurements for combinatorial studies of electrooxidation catalysts. The ability to measure the activity of catalyst surfaces toward the hydrogen oxidation reaction via tip−sample feedback is used to characterize the activity of PtxRuy and PtxRuyMoz catalysts as a function of composition and electrode potential. Multielement band electrodes containing various compositions of PtxRuy and PtxRuyMoz deposits are created via pulsed electrochemical deposition onto patterned substrates. Catalyst compositions are verified through a combination of Auger electron …