Application of non-metal doped titania for inverted polymer solar cells

A titanium dioxide porous network structure was synthesized using a poly(styrene-block-polyethylene oxide) diblock copolymer template. The influence of the titanium precursor concentration and annealing temperature on the obtained morphology was studied. Heterojunction solar cells consisting of TiO2 porous network structure and poly(2-methoxy-5-(2′-ethyl-hexyloxy)-p-phenylene vinylene) (MEH-PPV) were fabricated. The influence of the MEH-PPV layer thickness and device architecture on the solar cell performance was investigated. For an optimized device structure, a short-circuit current as high as 3.3 mA cm−2 is obtained under simulated solar illumination with an air mass AM 1.5 filter. The improved higher short-circuit current compared to other reports on MEH-PPV /TiO2 heterojunction cells can be attributed to improved morphology of the TiO2 layer.

The porous titanium dioxide network structure with adjustable average pore size were prepared. The different pore sizes were obtained by controlling the titanium precursor concentration. The porous anatase titania network structure with high surface area is thermally stable and uniform over the whole sample area. The use of these structures in organic solar cells yielded considerable improvements in the short circuit currents compared to previous reports on TiO2/polymer solar cells.