Civil Engineering Handbook

COCOCO j

Figure 1

Figure 1

Figure 2

EXPERIMENTAL:

Smooth electrodes: Polyciystalline Pt and Pt based alloys of selected compositions in the Pt-Ru-Os system (Figure 3) were prepared by arc-melting. All electrodes were prepared for voltammetric studies using the following regime: (1) Polish to 0.25pm; (2) Ultrasonically clean in Nanopure™ water, (3) Etch in aqua regia for 10 seconds; (4) Ultrasonically clean in Nanopure™ water and transfer to the electrochemical cell.

The potential vs. time program shown in Figure 4 was applied to each electrode in 0.5M H2SO< solution to investigate the CO tolerance of each electrode.

Ru 20 40 60 80 Os (at.%Os)

Figure 3

CO ADSORfTION EXPERIMENT

B: C0odsopnon300sec C Ar purging 900 sec D: H cdsxpfion & H, evouftn

In presence of CO E-: H, cuddaron in presence of CO E; CO aodaion ISMsoUg] F: Hocsoipfcn&H,evolu9Gnn obsenceofCO G: Hjottjerionm absence of CO