Yes.  The potential axis is arbitrary relative to a given reference electrode.  A cell is not like a passive resistor where 0 voltage results in 0 current.  It is impossible to know an interfacial potential absolutely. It can not be measured except relative to a second electrode placed in the solution.  Electrochemistry with one electrode is impossible.

Just because the terminal voltage is zero, it doesn't mean there are no potentials in the cell electrochemistry. If you short circuit a battery you will get a very large current even though the terminal voltage is zero. Your cell is not balanced Ag one side, AgCl the other so there will be a potential inside the cell driving the current.

Yes.  The potential axis is arbitrary relative to a given reference electrode.  A cell is not like a passive resistor where 0 voltage results in 0 current.  It is impossible to know an interfacial potential absolutely. It can not be measured except relative to a second electrode placed in the solution.  Electrochemistry with one electrode is impossible.

what about your open circuit potential vs. ref. ?

dear Ayan Sarkar,

your question may be somehow similar to  . . .  a problem of  "Air Crash Investigations" for airplanes with 2 altimeters.  So the altitude of an airplane (like W-electrode) is shown with reference the 

1) sea level (like R-electrode) and the

2) ground level (like C-electrode).

So, in order to simplify the problem, initially, ignore the Reference (R) electrode (Ag/AgCl) and consider only a simple 2-elements' circuit, i.e. elements s1, s2 (in series) where:

s1 = the source (potentiostat)

s2 = Working electrode (W)   //   Counter electrode (C)

The Reference (R) electrode (for a simple experiment) is useful to keep track of the (parametric) voltage VWR. So you may consider a (useful)  i-V replacing the nominal voltage VWC with the useful VWR.

Yes. Sea level is an interesting analogy with a reference electrode. For both we make relative measurements because we have no choice.  

Thank all of you for the answers. Meanwhile, I've studied and conducted few experiments and from those, I have found that a current flows from the CE to the WE or the vice versa to maintain the applied voltage difference between the WE and the RE. The direction of  the current depends on the type of the electrode material and electrolyte (i.e.redox potential of the electrolyte and the Fermi level of the WE). Are my findings true?

The direction of the net current depends on the sum of nonfaradic current and faradic current.

Remember, the current id determined entirely by what happens at the working electrode.

THAT CURRENT DETERMINES the current at the auxiliary electrode which is necessarily identical. Of course if the working electrode processes are overall reducing (cathodic) then the auxiliary electrode current is necessarily oxidative (anodic) and vice versa.  Unless the electrode is a semiconductor you need not worry much about the potential drop IN the electrode.   Solution resistance and the relative size of working and auxiliary electrodes will have an impact too... If the auxiliary electrode is much larger than the working electrode, the current density there will be much smaller than at the working electrode.   All of this is covered in ancient books by Kissinger and Heineman and by Bard and Faulkner.

Happy New Year...

dear Ayan Sarkar,

yes (q: Are my findings true?),  under normal conditions,

i.e. the chemical potential ui of the i carrier is between HOMO and LUMO in the specific electrolyte//electrode, system.

Note: In addition to the voltages of the electrodes mentioned previously,  it is sometimes useful to consider two more critical voltage levels VH, VL. They are produced from the HOMO, LUMO energy levels (EH, EL), which in voltage notation are : VH=EH/ne,  VL=EL/ne, (n=charge of carries, usually n=1).

You are sounding like a physical chemist or physicist! :)   Too many things are happening at once, especially when potential is scanned at various rates. Let's just say that most things that go on in electrochemistry do not fit any ideal conception, at least not very well.   Solid state physics and gas phase spectroscopy tend to conform better to theory in my experience.  In solution AND at surfaces, we have a lot happening in time and space. 

yes, you should have negative or positive current depends on the reaction occurs at this potential.

In electrochemistry, no current flow occurs only at the equilibrium potential (non polarized electrode)

Another way to think of this question is to recognize that if you use a different reference electrode, the zero on your plot will move.  Alaa makes a good point.  At equilibrium both oxidation and reduction reactions are continuing, but the net current is zero.

... a measurement at equilibrium (e.g. with zero net current, at a specific parametric Temperature) for a specific system, is the strongest evidence in order to form the scene of investigation resources about the electrical structure-scene of the system.

Respected all,

Actually, I'm dealing with some semiconductor nano material-electrode. One pristine material and other doped one. The doped one shows a negative current a 0V vs Ag/AgCl, but the pristine sample doesn't, during the i-t measurements. However, when the LSV is performed for each of them, both show  negative currents at 0V vs. Ag/AgCl and it happened over and over. Is there any discrepancy? 

During LSV, in the anodic scanning, species present in the electrolyte or inside the electrode can be oxidized and they will be reduced during the cathodic scanning. The applied 0 V vs Ag/AgCl could be more positive or negative in relation to the open circuit potential of each electrode vs the same reference electrode.

dear Ayan Sarkar,

you must note the electrode (system : semiconductor//electrolyte).