Issue 44, 2013

Enhancement of power conversion efficiency of dye-sensitized solar cells by co-sensitization of zinc-porphyrin and thiocyanate-free ruthenium(ii)-terpyridine dyes and graphene modified TiO2 photoanode

Abstract

A combination of a meso substituted zinc-porphyrin with two pyridyl groups and two benzoate groups at cis positions to each other (POR) with a mononuclear ruthenium(II) complex containing a 2,6-bis(1-methylbenzimidazol-2-yl)pyridine ligand and a carboxylic acid functionalized terpyridine ligand (SPS-G3) has been used as co-sensitizing system for the fabrication of dye-sensitized solar cells (DSSCs). The POR/SPS-G3 co-sensitized solar cell with a TiO2 photoanode displays enhanced short circuit current, open circuit voltage, and fill factor values (Jsc = 16.18 mA cm−2, Voc = 0.64 V, FF = 0.71, respectively), resulting in an overall power conversion efficiency (PCE) of 7.35%, which is superior to that for the DSSCs based on the individual dyes POR and SPS-G3. This is attributed to the improved light harvesting efficiency of the POR/SPS-G3 co-sensitizing system, which is evidenced by the incident photon-to-current efficiency (IPCE) spectrum of the co-sensitized solar cell. Further improvement of the PCE value of the co-sensitized solar cell (up to 8.15%) has been achieved by using a graphene modified TiO2 (G-TiO2) photoanode, instead of a pure TiO2 photoanode. Based on dark current measurements and electrochemical impedance spectra (EIS), the increased PCE value of the solar cell with the G-TiO2 photoanode can be attributed to suppression of charge recombination at the photoanode/dye/electrolyte interface and enhancement of electron transport in the photoanode. These results are in accordance with the longer electron lifetime exhibited by the G-TiO2 photoanode.

Graphical abstract: Enhancement of power conversion efficiency of dye-sensitized solar cells by co-sensitization of zinc-porphyrin and thiocyanate-free ruthenium(ii)-terpyridine dyes and graphene modified TiO2 photoanode

Article information

Article type
Paper
Submitted
22 May 2013
Accepted
04 Sep 2013
First published
06 Sep 2013

RSC Adv., 2013,3, 22412-22420

Enhancement of power conversion efficiency of dye-sensitized solar cells by co-sensitization of zinc-porphyrin and thiocyanate-free ruthenium(II)-terpyridine dyes and graphene modified TiO2 photoanode

G. D. Sharma, D. Daphnomili, K. S. V. Gupta, T. Gayathri, S. P. Singh, P. A. Angaridis, T. N. Kitsopoulos, D. Tasis and A. G. Coutsolelos, RSC Adv., 2013, 3, 22412 DOI: 10.1039/C3RA42537A

To request permission to reproduce material from this article, please go to the Copyright Clearance Center request page.

If you are an author contributing to an RSC publication, you do not need to request permission provided correct acknowledgement is given.

If you are the author of this article, you do not need to request permission to reproduce figures and diagrams provided correct acknowledgement is given. If you want to reproduce the whole article in a third-party publication (excluding your thesis/dissertation for which permission is not required) please go to the Copyright Clearance Center request page.

Read more about how to correctly acknowledge RSC content.

Social activity

Spotlight

Advertisements