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The performance of thin film optoelectronic devices comprised of lead chalcogenide (PbX) quantum dots (QDs) has seen rapid development since 2005. Lead chalcogenides have uniquely large dielectric constants and therefore large exciton Bohr radii that result in a significant degree of quantum confinement.[1] For example, PbX QDs are easily synthesized with band gaps ranging from 0.5 to 2.0 eV.[2–5] Such large Bohr Radii (18 and 47 nm for PbS and PbSe) and small effective masses for electrons and holes (∼ 0.09 m e) promote charge delocalization in QD films giving rise to an increase in charge carrier mobility and thus the conductivity. Field effect transistors in which current flows laterally, controlled by a gate bias, through a PbSe QD film on a Si wafer brought increased attention to PbX QD films. Soaking the film in hydrazine allows for an n-type gated response and control over the majority carrier type was demonstrated by thermal treatment which removes volatile hydrazine molecules resulting in p-type behavior.[6] Subsequently, Wang et al. directly demonstrated carrier type inversion in similar QD films through thermopower measurements.[7] In addition to short-chained amines like hydrazine and also butylamine,[8] simple thiol-terminated molecules aggressively remove the native oleate ligand, and allow for strong electronic coupling in QD arrays.[9–11] Along these lines, 1, 2-ethanedithiol (EDT) has received considerable attention in coupled films of PbS and PbSe QDs. 1, 4-and 1, 3-benzenedithiol work similarly well and have been reported to increase the air stability of films due to reduced volatility compared to hydrazine or EDT …