Photocurrent Enhanced by Singlet Fission in a Dye-Sensitized Solar Cell

0443599 - ÚOCHB 2016 RIV US eng J - Journal Article
Schrauben, J. N. - Zhao, Y. - Mercado, C. - Dron, P. I. - Ryerson, J. L. - Michl, Josef - Zhu, K. - Johnson, J. C.
Photocurrent Enhanced by Singlet Fission in a Dye-Sensitized Solar Cell.
ACS Applied Materials and Interfaces. Roč. 7, č. 4 (2015), s. 2286-2293. ISSN 1944-8244. E-ISSN 1944-8252
Institutional support: RVO:61388963
Keywords : photovoltaics * singlet fission * triplet * spectroscopy * charge transfer * photocurrent
Subject RIV: CF - Physical ; Theoretical Chemistry
Impact factor: 7.145, year: 2015

Investigations of singlet fission have accelerated recently because of its potential utility in solar photoconversion, although only a few reports definitively identify the role of singlet fission in a complete solar cell. Evidence of the influence of singlet fission in a dye-sensitized solar cell using 1,3-diphenylisobenzofuran (DPIBF, 1) as the sensitizer is reported here. Self-assembly of the blue-absorbing 1 with co-adsorbed oxidation products on mesoporous TiO2 yields a cell with a peak internal quantum efficiency of similar to 70% and a power conversion efficiency of similar to 1.1%. Introducing a ZrO2 spacer layer of thickness varying from 2 to 20 angstrom modulates the short-circuit photocurrent such that it is initially reduced as thickness increases but 1 with 1015 angstrom of added ZrO2. This rise can be explained as being due to a reduced rate of injection of electrons from the S1 state of 1 such that singlet fission, known to occur with a 30 ps time constant in polycrystalline films, has the opportunity to proceed efficiently and produce two T1 states per absorbed photon that can subsequently inject electrons into TiO2. Transient spectroscopy and kinetic simulations confirm this novel mode of dye-sensitized solar cell operation and its potential utility for enhanced solar photoconversion.
Permanent Link: http://hdl.handle.net/11104/0246339