Band-like transport, high electron mobility and high photoconductivity in all-inorganic nanocrystal arrays

Nat Nanotechnol. 2011 Apr 24;6(6):348-52. doi: 10.1038/nnano.2011.46.


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.

Publication types

  • Letter
  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Cadmium Compounds / chemistry*
  • Electric Conductivity
  • Electron Transport
  • Electrons*
  • Indium / chemistry*
  • Materials Testing
  • Nanoparticles / chemistry*
  • Nanotechnology / instrumentation
  • Photochemistry
  • Quantum Theory
  • Selenium / chemistry*
  • Selenium Compounds / chemistry*
  • Semiconductors
  • Sulfides / chemistry*
  • Surface Properties


  • Cadmium Compounds
  • Selenium Compounds
  • Sulfides
  • indium triselenide
  • Indium
  • cadmium sulfide
  • cadmium selenide
  • Selenium