Enhanced thermal stability of organic solar cells on nano structured electrode by simple acid etching

Abstract

The long-term thermal stability of organic photovoltaic device has been emerged as a crucial characteristic to satisfy the demand of industry requiring lifespan of 20 year. In this paper, etched indium-tin-oxide (ITO) nanoelectrodes are employed to enhance the thermal stability and power conversion efficiency in poly(3hexylthiophene):methanofullerene bulk-heterojunction solar cells. A simple etching process for the ITO electrode was carried out using a hydrochloric acid solvent in order to significantly increase the roughness of the ITO surface. This nanostructured ITO not only induced efficient light harvesting, but also acted as a barrier that suppressed the PCBM phase separation, resulting in the lifespan increased from 33 h to 77 h during thermal annealing.