Low-temperature solution-processed solar cells based on PbS colloidal quantum dot/CdS heterojunctions

Publication Type:

Journal Article

Source:

Nano Lett., ACS Publications, Volume 13, Issue 3, p.994-999 (2013)

ISBN:

1530-6984

Keywords:

2013, 2013 and earlier

Abstract:

PbS colloidal quantum dot heterojunction solar cells have shown significant improvements in performance, mostly based on devices that use
high-temperature annealed transition metal oxides to create rectifying
junctions with quantum dot thin films. Here, we demonstrate a solar cell
based on the heterojunction formed between PbS colloidal quantum dot
layers and CdS thin films that are deposited via a solution process at 80
°C. The resultant device, employing a 1,2-ethanedithiol ligand exchange
scheme, exhibits an average power conversion efficiency of 3.5%. Through a
combination of thickness-dependent current density-voltage
characteristics, optical modeling, and capacitance measurements, the
combined diffusion length and depletion width in the PbS quantum dot layer
is found to be approximately 170 nm.