Surfactant mediated growth of ZnO nanostructures and their dye sensitized solar cell properties

Abstract

Single crystalline and highly aligned ZnO nanorods, faceted microrods, nanoneedles and nanotowers were grown onto glass substrates by a facile aqueous chemical method at relatively low temperature (90 °C). Various structure directing agents or organic surfactants such as diaminopropane (DAP), polyacrylic acid (PAA) and polyethylenimine (PEI) were used to modify the surface morphology. The samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and optical absorption. It was found that, vertically aligned ZnO nanorods formation takes place with preferential orientation along (002) plane. The organic surfactants play an important role in modifying the morphology. The samples were further used to fabricate dye sensitized solar cells. The highest photocurrent (670 μA) and efficiency were observed for the ZnO:PEI sample.