Title: Enhanced photovoltaic performance with co-sensitization of porphyrin and an organic dye in dye-sensitized solar cells
Authors: Lan, Chi-Ming
Wu, Hui-Ping
Pan, Tsung-Yu
Chang, Chia-Wei
Chao, Wei-Shan
Chen, Chien-Tien
Wang, Chin-Li
Lin, Ching-Yao
Diau, Eric Wei-Guang
Department of Applied Chemistry
Institute of Molecular science
Issue Date: 1-Apr-2012
Abstract: We designed a stepwise approach for co-sensitization of a zinc porphyrin sensitizer (LD12) with a spirally configured organic dye (CD5) for dye-sensitized solar cells. The co-sensitized LD12 + CD5 device showed significantly enhanced V-OC and J(SC) relative to its individual single-dye sensitized devices. Upon optimization, the device made of the LD12 + CD5 system yielded J(SC)/mA cm(-2) = 16.7, V-OC/V = 0.74, FF = 0.73 and eta = 9.0%; this performance is superior to that of either individual device made from LD12 (eta = 7.5%) and CD5 (eta = 5.7%) under the same conditions of fabrication. To understand the effects of the potential shift and charge recombination on the cell performance, we measured charge-extraction (CE) and intensity-modulated photovoltage spectra (IMVS). Upon sensitization with each dye, the TiO2 potentials are similar, but co-sensitization causes the potential to shift down (cathodic shift). Charge recombination was significantly retarded for the co-sensitized system relative to each individual dye-sensitized system, to account for the enhanced V-OC for the former relative to the latter. A test of stability indicates a systematic trend between the LD12 + CD5 and LD12 devices; the performance of the co-sensitized device degraded only similar to 15% and remained stable during the period of 500-1000 h near 295 K.
URI: http://dx.doi.org/10.1039/c2ee21104a
ISSN: 1754-5692
DOI: 10.1039/c2ee21104a
Volume: 5
Issue: 4
Begin Page: 6460
End Page: 6464
Appears in Collections:Articles

Files in This Item:

  1. 000301984200023.pdf