1D Pd-Based Nanomaterials as Efficient Electrocatalysts for Fuel Cells - Low-cost Nanomaterials: Toward Greener and More Efficient Energy Applications - page 340

Fig. 21 Nyquist impedance
plots of formic acid oxidation
on PdAg-NW/GC (a) and
Pd/GC (b) electrodes in
0.1 M HClO 4 +0.5 M
HCOOH at various electrode
potentials. The solid lines
show some representative fits
to the experimental data
based on the equivalent
circuits. c Charge-transfer
resistance (R CT ) of formic
acid electrooxidation at
different electrode potentials
on PdAg-NW/GC (black
curve) and Pd/GC (red curve)
electrodes. Reprinted from
Ref. [ 70 ] with permission by
the American Chemical
Society

(a)

30

25

- 0.10 V
0.00 V
+ 0.10 V
+ 0.20 V
+ 0.30 V
+ 0.40 V
+ 0.50 V
+ 0.60 V
+ 0.65 V
+ 0.80 V
+ 0.90 V
fitting

20

15

10

5

0

-5

-20 -10 0 10 20 30 40

(b)

100

-0.10 V
0.00 V
+0.10 V
+0.20 V
+0.30 V
+0.40 V
+0.50 V
+0.60 V
+0.65 V
+0.70 V
+0.80 V
+0.90 V
fitting

80

60

40

20

0

0 10 20 30 40

Z re (K Ω )

(c)

400

Pd/C

300

200

100

0

-100

AgPd

-200

-.2 0.0 .2 .4 .6 .8 1.0

E (V vs Ag/AgCl)

Recently, Song et al. [ 78 ] reported the fabrication of Pd nanotube electrodes by
means of electrodeposition method as a function of applied current density. From
the TEM and SEM images (Fig. 22 ) of the Pd array electrodes electrodeposited
using different current densities, it can be seen that all the products exhibit tubular
arrays having an average diameter of *220 nm and different lengths. Note that the
surface of the as-synthesized Pd-NT becomes rougher with the increase in current