Selvarani, G. and Sahu, A.K. and Kiruthika, G.V.M. and Sridhar, P. and Pitchumani, S. and Shukla, A.K.
(2009)
PEFC Electrode with Enhanced Three-Phase Contact
and Built-in Supercapacitive Behavior.
Journal of the Electrochemical Society, 156 (1).
pp. 118-125.
ISSN 0013-4651
Abstract
Hydrous ruthenium oxide, which exhibits both protonic and electronic conduction, is incorporated in the cathode electrocatalyst
layer of the membrane electrode assembly for polymer electrolyte fuel cells (PEFCs). The supercapacitive behavior of ruthenium
oxide helps realize a fuel cell–supercapacitor hybrid. Platinum (Pt)nanoparticles are deposited onto carbon-supported hydrous
ruthenium oxide and the resulting electrocatalyst is subjected to both physical and electrochemical characterization. Powder X-ray
diffraction and transmission electron microscopy reflect the hydrous ruthenium oxide to be amorphous and well-dispersed onto the
catalyst. X-ray photoelectron spectroscopy data confirm that the oxidation state of ruthenium in Pt anchored on carbon-supported
hydrous ruthenium oxide is Ru4+. Electrochemical studies, namely cyclic voltammetry, cell polarization, intrinsic proton conductivity,
and impedance measurements, suggest that the proton-conducting nature of hydrous ruthenium oxide helps extend the
three-phase boundary in the catalyst layer, which facilitates improvement in performance of the PEFC. The aforesaid PEFC
operating with hydrogen fuel and oxygen as oxidant shows a higher power density �0.62 W/cm2 @ 0.6 V� in relation to the PEFC
comprising carbon-supported Pt electrodes �0.4 W/cm2 @ 0.6 V�. Potential square-wave voltammetry study corroborates that the
supercapacitive behavior of hydrous ruthenium oxide helps ameliorate the pulse-power output of the fuel cell.
Actions (login required)
|
View Item |