Charge transport and electroluminescence of lead chalcogenide nanocrystal and nanowire thin films in field-effect transistors

• Applicant: Professorin Dr. Jana Zaumseil
• Subject Area: Physical Chemistry of Solids and Surfaces, Material Characterisation
• Term: from 2010 to 2015
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 181452398

Near-infrared light (800-2000 nm) is of great technological importance in areas such as optical telecommunication, chemical sensing and night vision. Inorganic semiconductor nanocrystals (quantum dots) such as PbSe and PbS are efficient near-infrared emitters that are solution-processable and allow for size-dependent tuning of their narrow band emission. We propose to realize ambipolar field-effect transistors of thin films of lead chalcogenide (PbS, PbSe) nanocrystals and nanowires to allow electron-hole recombination and thus near-infrared electroluminescence. We aim to accomplish efficient charge transport by exchanging long insulating nanocrystal ligands with small molecules (e.g. hydrazine) and metal chalcogenides (e.g. Sn2S64-). As a means to promote injection of both holes and electrons and accumulation of large charge carrier densities in field-effect transistors we will use electrolyte-gating with ionic liquids instead of traditional gate dielectrics. Current-voltage and emission characteristics of these devices will provide insights into the charge transport and recombination physics of nanocrystal solids.

• DFG Programme: Research Grants