Enhancement of hybrid solar cell performance by polythieno [3,4-b]thiophenebenzodithiophene and microplasma-induced surface engineering of silicon nanocrystals

Abstract

We have developed a room temperature fabrication technique for hybrid bulk heterojunction solar cells based on silicon nanocrystals (Si-ncs) embedded in polythieno[3,4-b]thiophenebenzodithiophene (PTB7) and that exhibit a high open-circuit voltage exceeding 1 V. This type of device outperforms the open-circuit voltage of analogous devices based on Si-ncs within poly(hexylthiophene) (P3HT). We also demonstrate that three dimensional surface engineering of Si-ncs by microplasma processing in ethanol can be used to enhance the electronic interactions with PTB7, without using any surfactant, and increasing the power conversion efficiency. © 2012 American Institute of Physics.