Functionalized nanodiamond as a charge transporter in organic solar cells

We demonstrate for the first time the efficiency improvement of poly(3-hexylthiophene) (P3HT)–fullerene (C60) bulk heterojunction photovoltaic cells by the introduction of functionalized nanodiamonds (NDs) into the photoactive layer. A novel covalently bonded C60ND composite was synthesized via a microwave induced functionalization approach. As compared to control devices with only C60, the addition of carboxylated ND resulted in 53% improvement in short circuit current density Jsc. Such a device design takes advantages of both C60 for electron accepting and ND for efficient electron transport. The results indicate that C60 decorated NDs are promising additives for the performance enhancement of polymer photovoltaic cells.

► We demonstrate the efficiency improvement by the introduction of functionalized nanodiamonds (NDs) into the photoactive layer. ► The introduction of ND in the acceptor phase led to 71% improvement in short circuit current density Jsc. ► The fullerene–NDCOOH complex was synthesized via a microwave induced functionalization approach.