ZnO and conjugated polymer bulk heterojunction solar cells containing ZnO nanorod photoanode

Hybrid solar cells based on poly(3-hexylthiophene) (P3HT) and ZnO nanoparticle bulk heterojunctions (BHJ) combined with ZnO nanorod arrays were fabricated and analyzed. The dispersion of ZnO nanoparticles in P3HT is assisted by dye molecules, which function as a surface modifier for ZnO nanoparticles to improve compatibility between ZnO nanoparticles and P3HT. Compared to the ZnO nanorod/P3HT devices, the optimized cells with the ZnO nanoparticles dispersed in P3HT can significantly increase the short-circuit current and the overall power conversion efficiency from 1.36 mA cm(-2) to 2.51 mA cm(-2) and from 0.18% to 0.45% with 625 nm long ZnO nanorod arrays, respectively. The novel scheme of using the light-absorbing dye molecules both as light absorber and as surfactant for ZnO nanoparticles presents a facile route towards forming bulk heterojunction hybrid solar cells based on semiconducting nanomaterials and conjugated polymers.