Abstract
In order to fabricate photovoltaic (PV) cells incorporating light-trapping electrodes, flexible foil substrates, or more than one junction, illumination through the top-contact (i.e.: non-substrate) side of a photovoltaic device is desirable. We investigate the relative collection efficiency for illumination through the top vs. bottom of PbS colloidal quantum dot (CQD) PV devices. The external quantum efficiency spectra of FTO/TiO2/PbS CQD/ITO PV devices with various PbS layer thicknesses were measured for illumination through either the top (ITO) or bottom (FTO) contacts. By comparing the relative shapes and intensities of these spectra with those calculated from an estimation of the carrier generation profile and the internal quantum efficiency as a function of distance from the TiO2 interface in the devices, a substantial dead zone, where carrier extraction is dramatically reduced, is identified near the ITO top contact. The implications for device design, and possible means of avoiding the formation of such a dead zone, are discussed.
©2010 Optical Society of America
Full Article | PDF ArticleMore Like This
Yulan Fu, Abay G. Dinku, Yukihiro Hara, Christopher W. Miller, Kristina T. Vrouwenvelder, and Rene Lopez
Opt. Express 23(15) A779-A790 (2015)
Ebuka S. Arinze, Botong Qiu, Nathan Palmquist, Yan Cheng, Yida Lin, Gabrielle Nyirjesy, Gary Qian, and Susanna M. Thon
Opt. Express 25(4) A101-A112 (2017)
Vahid A. Akhavan, Matthew G. Panthani, Brian W. Goodfellow, Dariya K. Reid, and Brian A. Korgel
Opt. Express 18(S3) A411-A420 (2010)