Control of Thickness of PEDOT Electrodeposits on Glass/ITO Electrodes from Organic Solutions and its Use as Anode in Organic Solar Cells

Poly-ethylendioxythiophene (PEDOT) was electropolymerized from the monomer EDOT in acetonitrile (ACN) containing Bu₄N⁺ClO₄^-, BF₄^- or PF₆^- ions as supporting electrolyte. The electrode used was transparent electrodes (Glass/ITO) in order to generate the anode of an organic solar cell (OSC). Potentiodynamic and potentiostatic electropolymerization techniques were used to make the conducting polymer deposits (E-PEDOT), which were obtained as a thin film onto the ITO surface. It was possible to control the thickness of the electrodeposited films in the range of 15 to 200 nm measured by AFM. With the thinner films (until 100 nm), it was observed that its absorbance at 700 nm was linearly dependent with their thickness and it was possible to obtain an equation that was used to measure the films thickness of future experiments. The E-PEDOT films were successfully used for constructing OSC's and the efficiency values found were equivalent or slightly superior to those found with the classical PEDOT:PSS anode.