Catalysts reversal-tolerant

Ye S (2008) Reversal-tolerant catalyst layers, hi Zhang J (ed) PEM fuel cell electrocatalysts and catalyst layers fundamentals and application. Springer, London... 

In addition to enhancing the presence of water at the anode through modifications to the anode structure, a PEM fitel cell can be made more tolerant to voltage reversal by incorporating an additional catalyst, a water electrolysis (oxygen evolution reaction, OER) catalyst, at the anode to promote the electrolysis of water [14-16, 18]. In this way, more of the current forced through the cell may be consumed by the electrolysis of water than by the oxidation of the anode components. In a reversal-tolerant fuel cell, the anode comprises a first catalyst composition for evolving protons from the fuel and a second catalyst composition for water electrolysis. 

To improve voltage reversal tolerance of PEM fuel cells, water electrolysis catalysts have been incorporated into anode stractures by Johnson Matthey and Ballard Power Systems [12-17]. In such a reversal-tolerant fuel cell, the anode comprises a first catalyst composition for evolving protons from the fuel and a second catalyst composition for water electrolysis. 

Further voltage-reversal tolerance can be obtained by 1) employing a eatalyst support that is more resistant to oxidative corrosion than conventional eatalyst supports, 2) using certain anodes with a higher catalyst loading or coverage on a corrosion-resistant support, and 3) incorporating an additional or second catalyst... 

Ye S, Beattie P, Campbell SA, Wilkinson DP. Anode catalyst compositions for a voltage reversal tolerant fuel cell. US Patent Appl 2004/0013935. 

Knights S D, Taylor J L, Wilkinson D P and Campbell S A (2001), Supported Catalysts for the Anode of a Voltage Reversal Tolerant Fuel Cell. PCT WO 01/15254 A2, 01 March 2001. 

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