Electrical conductivity of chlorophyll with polythiophene thin film on indium tin oxide as P-N heterojunction solar cell

Abstract

This work was focused on the study of electrical conductivity to the combination of Polythiophene thin film (PT) and Chlorophyll thin film (CHLO) by layered on Indium Tin Oxide substrate (ITO) as p-n heterojunction solar cell. Polythiophene thin film is deposited to the ITO substrate by using electrochemistry method. Chlorophyll thin film is coated on Polythiophene thin film by using the spin coating method. Current and voltage of ITO/PT/CHLO thin film is measured in the dark and under different light intensity by using the four point probe. The result shows that Polythiophene thin film is successfully coated with Chlorophyll on ITO substrate with different thicknesses. Electrical conductivity in the dark showed an increasing with the increasing of Polythiophene thin film thickness. While, with the increasing of Chlorophyll thin film thickness, electrical conductivity in the dark is consecutively change. Electrical conductivity under different intensity of light increased with the increasing of light intensity. Electrical conductivity under intensity of light are diminished with the increasing of Polythiophene thin film thickness. While electrical conductivity is increase with the increasing of the light intensity and the increasing of Chlorophyll thin film thickness. In conclussion, combination of the thinnest Polythiophene thin film with the thickest Chlorophyll thin film produce the highest electrical conductivity reach up to ± 0.1 Sm-1 (raise 22% under illumination compared to the electrical conductivity in the dark condition). This study is suitable to generate a solar cell.