title: Band-like transport, high electron mobility and high photoconductivity in all-inorganic nanocrystal arrays.
abstract: Flexible, thin-film electronic and optoelectronic devices typically involve a trade-off between performance and fabrication cost. For example, solution-based deposition allows semiconductors to be patterned onto large-area substrates to make solar cells and displays, but the electron mobility in solution-deposited semiconductor layers is much lower than in semiconductors grown at high temperatures from the gas phase. Here, we report band-like electron transport in arrays of colloidal cadmium selenide nanocrystals capped with the molecular metal chalcogenide complex In(2)Se(4)(2-), and measure electron mobilities as high as 16 cm(2) V(-1) s(-1), which is about an order of magnitude higher than in the best solution-processed organic and nanocrystal devices so far. We also use CdSe/CdS core-shell nanoparticles with In(2)Se(4)(2-) ligands to build photodetectors with normalized detectivity D* > 1 × 10(13) Jones (I Jones = 1 cm Hz(1/2) W(-1)), which is a record for II-VI nanocrystals. Our approach does not require high processing temperatures, and can be extended to different nanocrystals and inorganic surface ligands.
authors.affiliation: Department of Chemistry and James Frank Institute, University of Chicago, Chicago, Illinois 60637, USA.
authors.forename: Jong-Soo
authors.initials: JS
authors.lastname: Lee
authors.forename: Maksym V
authors.initials: MV
authors.lastname: Kovalenko
authors.forename: Jing
authors.initials: J
authors.lastname: Huang
authors.forename: Dae Sung
authors.initials: DS
authors.lastname: Chung
authors.forename: Dmitri V
authors.initials: DV
authors.lastname: Talapin
mesh_terms: D019187:Cadmium Compounds / Q000737:chemistry*; D004553:Electric Conductivity; D004579:Electron Transport; D004583:Electrons; D007204:Indium / Q000737:chemistry*; D008422:Materials Testing; D053758:Nanoparticles / Q000737:chemistry*; D036103:Nanotechnology / Q000295:instrumentation; D010777:Photochemistry; D011789:Quantum Theory; D012643:Selenium / Q000737:chemistry*; D018036:Selenium Compounds / Q000737:chemistry*; D012666:Semiconductors; D013440:Sulfides / Q000737:chemistry*; D013499:Surface Properties
chemical_list: D019187:Cadmium Compounds; D018036:Selenium Compounds; D013440:Sulfides; C542684:indium triselenide; D007204:Indium; C034939:cadmium sulfide; C058667:cadmium selenide; D012643:Selenium