Electrochemical codeposition of poly(thieno[3,2-b]thiophene) and fullerene: An approach to a bulk heterojunction organic photovoltaic device

An electrochemical approach was developed to fabricate polymer solar cell. Poly(thieno[3,2-b]thiophene) and fullerene were codeposited by cyclic voltammetry from the solution containing corresponding monomers. The composition could be altered by changing potential range and was monitored by UV–Vis–NIR spectroscopy. Morphology and phase separation were studied by AFM revealing formation of the bulk heterojunctions. For the device fabrication the codeposition onto electropolymerized PEDOT layer was done without destructive interference. Voc of 0.3 V and Jsc of 35 μA/cm2 were measured under standard AM 1.5 conditions.

► Polymer solar cell was fabricated by electrochemical depositions.
► Fullerene and poly(thieno[3,2-b]thiophene) were codeposited electrochemically.
► Layer of PEDOT nanofibers was electropolymerized of ITO surface.
► Composition and oxidation states were controlled electrochemically.