Ultrahigh density array of CdSe nanorods for CdSe/polymer hybrid solar cells: enhancement in short-circuit current density

We fabricated CdSe/poly(3-hexylthiophene) (P3HT) hybrid solar cells with ultrahigh density array (4 × 1011in−2) of the CdSe nanorods having a length of ∼100 nm, a diameter of ∼20 nm, and an inter-distance of neighboring nanorods of ∼20 nm. The vertically oriented CdSe nanorods on indium tin oxide-coated glass were prepared by electrodeposition into a nanoporous template made of polystyrene-block-poly(methyl methacrylate) copolymer (PS-b-PMMA) thin film. The short-circuit current of this device was three-times greater than that of another solar cell prepared by CdSe/P3HT bilayer film, indicating that more efficient charge separation at the interface and facilitated charge transport were achieved through the vertically oriented CdSe nanorods. The power conversion efficiency of the solar cell based on CdSe nanorod array/P3HT hybrid was twice greater than that of another based on CdSe/P3HT bilayer films.