Patent ID: 8759816

Claim:
A device, comprising: a first electrode; a layer that includes a plurality of semiconductor nanoparticles configured to absorb incident light resulting in the production of electron-hole pairs; and a second electrode, the second electrode forming a metal-semiconductor junction with the layer that includes the plurality of semiconductor nanoparticles, the metal-semiconductor junction being configured to produce a built-in electric field over a depletion region formed between the second electrode and the layer of colloidal nanoparticles; wherein the semiconductor nanoparticles are bandgap-tuned via the quantum size effect; wherein electrons are to be swept via the action of the built-in electric field to the second electrode in an average transit time less than the time for electrons to recombine; and wherein holes are to be swept via the action of the built-in electric field to the first electrode in an average transit time less than the time for holes to recombine.