Surface treatment of nanocrystal quantum dots after film deposition

A photoelectronic device, comprising:

• a porous substrate;
• a population of quantum dots bearing exchange ligands and surmounting the substrate,
• at least some of the population of quantum dots having been contacted with a composition under such conditions so as to effect a reduction in the number of first ligands bound to the surface of the quantum dots and an increase in the number of exchange ligands bound to the surface of the quantum dots,
• the substrate being in electronic communication with a first electrode, and
• the device being configured so as to be capable of exposing the substrate to illumination;
• and
• an electrolyte, a hole transfer material, or both, that places the substrate and the first electrode in electronic communication with one another.

A method of constructing a device, comprising:

• contacting a population of quantum dots with an exchange composition that comprises an acid and at least one exchange ligand,
• the population of quantum dots surmounting a porous substrate,
• the population of quantum dots comprising at least one first ligand bound to a surface of a quantum dot,
• the contacting being performed under such conditions that the at least one first ligand is exchanged with the at least one exchange ligand,
• placing the porous substrate into electronic communication with a first electrode,
• configuring the device so as to be capable of exposing the porous substrate to illumination;
• and
• introducing an electrolyte, a hole transfer material, or both, so as to place the porous substrate and the first electrode in electronic communication with one another.

A method of constructing a device, comprising:

• contacting a population of quantum dots with an exchange composition that comprises at least one exchange ligand,
• the population of quantum dots surmounting a porous substrate,
• the population of quantum dots comprising at least one first ligand bound to a surface of a quantum dot,
• the quantum dot comprising CdO, CdS, CdSe, CdTe, HgO, HgS, HgSe, HgTe, Al2Se3, Ga2Se3, In2Se3, Sb2S3, Sb2Se3, Sb2Te3, SnSe, SnTe, PbO, PbO2, PbS, PbSe, PbTe, AlSb, GaAs, GaSb, or any combination thereof,
• the contacting being performed under such conditions that the at least one first ligand is exchanged with the at least one exchange ligand;
• placing the porous substrate into electronic communication with a first electrode;
• configuring the device so as to be capable of exposing the porous substrate to illumination;
• and
• introducing an electrolyte, a hole transfer material, or both, so as to place the porous substrate and the first electrode in electronic communication with one another.