Effect of interfacial properties and film thickness on device performance of bilayer TiO2-poly(1,4-phenylenevinylene) solar cells prepared by spin coating

An optimized bilayer solid state solar cell is fabricated from poly[1,4-{2-methoxy-5(2′-ethylhexyloxy)}phenylene-vinylene] (MEH-PPV) and TiO2 by spin coating. Optimal and reproducible device performance has been achieved by adjusting the polymer/TiO2 layer thickness, fabricating devices under an inert atmosphere and improving the polymer/gold contact. These devices showed very small leakage currents in the dark and an open circuit voltage of 0.8 V was recorded. The effect of interfacial properties, incident light intensity and irradiation time on device performance are also discussed.