Ligand engineering in hybrid polymer:nanocrystal solar cells

Blends of semiconducting polymers and inorganic semiconductor nanocrystals are receiving renewed interest as a type of inexpensive, solution-processed third generation solar cell. In these hybrid bulk heterojunctions (BHJs), the interfacinating factor in the overall performance of the resulting devices. Paramount to this interface is the ligand landscape on the nanocrystal surface, which as a ree between the disparate organic and inorganic phases is a domsult of the inherently large surface area to volume ratio of the nanocrystals, has a significant spatial and electronic influence on the boundary between the donor polymer and acceptor nanocrystal. We have investigated the importance of this three-part polymer/ligand/nanocrystal interface by studying the ligand effects in hybrid BHJ solar cells. In this article, we highlight the major research advances and the state-of-the-art in hybrid BHJ solar cells with respect to ligand engineering, as well as outline future research avenues deemed necessary for continued technological advancement.