Characterization of Electrodes and Electrocatalysts

A four-point probe method to measure resistivity of a layer. 

Fuel cell electrodes can be examined for their electrocatalytic behavior by ex situ or in situ voltammetry tests. In the case of ex situ tests, also known as half-cell tests, the properties of the electrode are evaluated using a standard three-electrode cell where an aqueous solution (e.g., perchloric acid) simulates the proton-conducting electrolyte in a PEMFC. Half-cell tests are a convenient and relatively fast method of screening electrocatalysts however. 

For characterization of low-temperature fuel cell wifh platinum electrodes, the following reactions are generally used the hydrogen adsorption/ desorption (HAD), 

The ECSA of the Pt catalyst is calculated using the following equation where 

Cyclic voltammogram of PEM fuel cell catalyst layer for ECSA analysis by hydrogen adsorption/desorption. 

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