Fabrication of organic photovoltaic cells with double-layer ZnO structure

The fabrication process of a photovoltaic cell with a structure of indium-tin-oxide (ITO)/double ZnO/C60/poly(3-hexylthiophene) (PAT6)/Ag has been investigated. The C60/PAT6 heterojunction of this cell was fabricated by spin-coating a chloroform solution of PAT6 onto the C60 thin film formed on double-layer ZnO-coated ITO. The fabrication of this double-layer ZnO was a new method, which was a composite of a sputtered ZnO layer and oriented zinc oxide nanograins layer fabricated at low temperature (343 K). Insertion of the double-layer ZnO in the photovoltaic cells produced enhanced performance with the power conversion efficiency of 1.31% under AM1.5 illumination.