Solvent Dependence of Interpenetrating Interface Formation in Organic Photovoltaic Cells with Heterojunction of Conducting Polymer and C_(60)

摘要

Optical and photovoltaic properties of a photovoltaic cell with a structure of indium-tin-oxide(ITO)/C_(60)/poly(2-methoxy-5-(2′-ethylhexyloxy)-1,4-phenylenevinylene) (MEH-PPV)/Au have been investigated. The C_(60)/MEH-PPV heterojunction of this cell was fabricated by spin-coating the solution of MEH-PPV onto the C_(60) thin film formed on ITO. Fabricated by this method, the photovoltaic cell has demonstrated a high efficiency, depending on the organic solvents used in the spin-coating process. From the optical properties and the direct observation of the C_(60)/MEH-PPV interface, it has been clarified that such a high photovoltaic performance originates from the interpenetrating interface of MEH-PPV and C_(60), the morphology of which depends on the solvent used in the fabrication process of the MEH-PPV film.