Semiconductor Conjugated Polymer-Quantum Dot Nanocomposites at the Air/Water Interface and Their Photovoltaic Performance

Organic-inorganic nanocomposites consisting of electroactive conjugated polymer, poly(3-hexylthiophene) (P3HT), intimately tethered on the surface of semiconductor CdSe quantum dot (i.e., P3HT-CdSe nanocomposites) at the air/water interface formed via Langmuir isotherms were explored for the first time. The P3HT-CdSe nanocomposites displayed a high pressure plateau (similar to 10.5 mN/m) in the Langmuir isotherm, illustrating their complex packing at the air/water interface. The packing of the Langmuir-Blodgett (LB) depositions of nanocomposites was revealed by AFM measurements. Furthermore, photovoltaic devices fabricated from the LB depositions of the P3HT-CdSe nanocomposites exhibited a relatively high short circuit current, I-sc, while maintaining a thin film profile. These studies provide insights into the fundamental behaviors of semiconductor organic-inorganic nanocomposites confined at the air/water interface as well as in the active layer of an organic-based photovoltaic device.