Structural Effects on Electrocatalysis by Pt Effect of Particle Size

Some of the first investigations towards elucidating particle size and stractural dependence were reported by Zeliger and Bett et. al. These studies concluded that platinum atoms at the 

These investigations revealed that the adsorptive morphology of the crystallites were paramount in the observed variations of ORR activity with specific surface area of platinum. These results therefore supported the earlier contention by Kinoshita, where correlation was made with the statistics of the presence of sites with different coordination numbers as a function of particle size. A later publication by the same group provided further support, with an 

Alloy Electrocatalysts Electronic and Stmctnral Effects on Electrocatalytic Properties of Platinnm Alloys 

The unique direct spectroscopic information obtainable from XANES data with the new analysis technique is highlighted here. Data have been taken at both the cathode (oxygen reduction) and at the anode (hydrogen or methanol oxidation). 

The amount of specifically adsorbed phosphate anions in the PAFC is much larger than of the (bi)sulfate anions in the PEMFC. The PEM membrane is specifically constmeted to keep the Pt electrode free of anions, while in contrast phosphate anions are known to directly adsorb to high coverage. The amount of chemisorbed OH tracks approximately with the fuel cell currents, the PAFC having low adsorption of OH at 0.85 V RHE while the PEMFC 

---

Structural Effects on Electrocatalysis by Pt Effect of Particle Size... 

---