Loss of Platinum Surface Area Due to Agglomeration

Loss of catalyst electrochemical surface area (ECSA), as discussed above, could be caused by Pt dissolution and migration into the membrane. In addition, increase in Pt particle size during fuel cell operation is another cause of ECSA loss in the catalyst layer. Loss of Pt surface area vs. time during fuel cell operation has been observed in both the phosphoric acid fuel cell [87-89] and PEMFC operations [9, 33, 90]. An increase in Pt particle size from 2-3 mn up to more than 10 mn during durability testing in the catalyst layer has been reported, determined by X-ray diffraction [46] or TEM image analysis [9, 33-38, 90]. 

Samples Surface area (mVg Pt) from TEM Surface area (m /g Pt) from EPSA measurement 

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