文档介绍：Experimental class on “ Fuel Cell and Electrochemistry
Experiment setup
Equipment: CHI760D electrochemical station
Th62
Peak voltage difference (mV)
71
66
68
72
75
76
79
79
From the CV curves, fill the table
3)
4) According to the result, describe why curves shows certain trend, and how peak current and peak voltage difference change with scan rate?
Answer: From above data and curve, we can obtain:
At a fixed scan rate : (1).from initial positive voltage to more reductive values, the current begin
to flow, then reach a peak ipc and decrease eventually. (2).when voltage moves back, the equilibrium positions gradually converting electrolysis product (Fe 2+) back to reactant (Fe 3+), the current flow is from the solution species back to the electrode and so occurs in the opposite
sense to the forward. The process has another current peak ipa. It has same reason of linear sweep voltammetry.
At different scan rate, the ratio of peak current ip c/ip a is about equal to 1 ( —).
At different scan rate, the position of peak voltage do not alter greatly C Ep is about a constant (66--79).
<mV/s)
20
50
100
200
300
400
500
600
1/2
V
(mV/s) 1/2
10
20
Ip (uA)
Ep(V)
Ep '(mV)
71
66
68
7