Enhanced Performance of a Polymer Solar Cell upon Addition of Free-Standing, Freshly Etched, Photoluminescent Silicon Nanocrystals

Abstract

We demonstrate an organic–inorganic hybrid solar cell using poly(3-hexylthiophene) (P3HT)/[6,6]-phenyl-C61-butyric acid methyl ester (PCBM) and silicon nanocrystals (Si-NCs). To achieve an enhanced response in the hybrid layer, Si-NCs were freshly etched and blended with P3HT/PCBM. The incorporation of Si-NCs into the bulk heterojunction structure induced the coupling of optical excitation between the polymers and Si-NCs and led to an extended optical excitation response. A hybrid solar cell exhibited a 26% increase in JSC relative to an identical cell prepared without the Si-NCs. Consequently, improved power conversion efficiency is obtained by the addition of Si-NCs into polymers.