What is the potential window, which you have already tried? Perhaps you have to go to more positive potentials. I would firstly measure the blanc (background) solution in the largest potential window as possible, then background + your Schiff base at ca. 1mM at the same potential window, and then background +Schiff bas + ferrocene under the same conditions.

you  check whatever Mr. Nataliya said. you can change the reference electrode , used Ag/AgCl double jacket reference electrode also.

Thank you, potential range was 0 to 1.6 volts and actually I first measured background and then background+ferrocene after this I measured Background+Ferrocene+Schiff base. Does it matter if i measure with ferrocene first and then our molecule. I added very less amount of  ferrocene so that intensity of our molecule should not be lost in front of ferrocene.

If you are sure, that ferrocene does not affect the electrochemical conversion of your Schiff base (even at small concentrations it can act as a catalyst, mediator, inhibitor etc.), then teh order of measurement does not matter. If you have an uncompletely characterized substance, I would mesure CV and then add ferrocene in your working solution, i.e. directly into the cell.

Most of organic compounds are electrochemically silent (do not show any CV peaks). Electrochemistry is not a "magic" tool. You may try to use Pt- or Au-working electrodes, but probably you will not see any peaks. 

Thank you Yurii V, though electrochemistry is not a magic tool for finding the HOMO and LUMO energy level i have to go for electrochemistry studies only, but if there is any other way please suggest. thank you.

Is the Schiff Base studied electroactive in the potential window used? If not, you should not expect to see any redox Peaks in CV. Could you give some detail regarding the molecular structure? Why did you do electrochemical Measurements in an organic solvent? Is your molecule water-insoluble? 

Dear Qijin Chi,

The molecule is water insoluble. Please find the attached file for molecular structure.

Thank you.

Hi Suman,

I cannot see this molecule should be electroactive after checking its structure. So, the question is: what is exact purpose that you use electrochemistry to study this molecule? Do you use this molecule as dye-sensitized agent for solar cells?  

Yes sir,

I wanted to use it for DSSC application only. So to find energy levels i did that experiment.

Hi Suman,

If that's the case, you can try to directly measure photocurrent generation in photoelectrochemical environment. I attach one of our papers, and hopefully it is helpful for you. Good luck!

hello 

suman 

you can use instead of glassy carbon working  use as a working electrode platinum disk electrode high surface area it will come  

Thank you all. 

You can incrase the sensib of the working electrode by the deposition of carbon nanotubes. It showed increasing sensitivity