Patent ID: 8258398

Claim:
A heterojunction photovoltaic cell, comprising: a nanoporous substrate having a substrate surface; a transparent conducting oxide disposed on at least a portion of the nanoporous substrate to faun a first electrode; a semiconductor oxide layer having a wide band gap and disposed adjacent the transparent conducting oxide; a nanolaminate film deposited on the substrate surface, and the nanoporous substrate, the transparent conducting oxide and the nanolaminate film forming a nanowire; a sensitizer dye having sensitizer dye molecules and, disposed on at least a portion of an interior portion of the nanowire; and an insulating alumina layer deposited on the interior portion of the nanowire between the sensitizer dye molecules and onto exposed portions of the semiconductor oxide layer, such that the sensitizer dye molecules are not coated with the alumina layer; a redox shuttle layer coupled to the sensitizer dye and the insulating alumina layer coating being between the molecules of the sensitizer dye which are thereby exposed to the redox shuttle layer adjacent thickness-wise the sensitizer dye and attached to the semiconducting oxide layer, thereby enabling the sensitizer dye to function unaffected, but insulating other areas of the semiconductor oxide layer in contact with the redox shuttle, thereby decreasing loss of electrons from recombination.