I am working with a screen-printed sensor and when I plot the CV curve I am getting additional small peaks and dips beside the oxidation and reduction peaks. Can you please tell me the reason behind it and ways to solve it?
Additional peaks like these seem to be associated with the concentration of an external agent, such as oxygen in appreciable concentrations. What pH did you work at? Did you purge the solution with inert gas before measuring?
See these works, you can give some direction:
Electrochemical Study of Oxygen Reduction Reaction on Natural Chalcopyrite in Sulfuric Acid and Ferric Solutions Int. J. Electrochem. Sci., 11 (2016) 34 - 44 http://www.electrochemsci.org/papers/vol11/110100034.pdf
Innovative catalyst design for oxygen reduction reaction for fuel cells