Multifunctional Iodide-Free Polymeric Ionic Liquid for Quasi-Solid-State Dye-Sensitized Solar Cells with a High Open-Circuit Voltage.

Abstract

A polymeric ionic liquid, poly(oxyethylene)-imide-imidazolium selenocyanate (POEI-IS), was newly synthesized and used for a multifunctional gel electrolyte in a quasi-solid-state dye-sensitized solar cell (QSS-DSSC). POEI-IS has several functions: (a) acts as a gelling agent for the electrolyte of the DSSC, (b) possesses a redox mediator of SeCN(-), which is aimed to form a SeCN(-)/(SeCN)3(-) redox couple with a more positive redox potential than that of traditional I(-)/I3(-), (c) chelates the potassium cations through the lone pair electrons of the oxygen atoms of its poly(oxyethylene)-imide-imidazolium (POEI-I) segments, and (d) obstructs the recombination of photoinjected electrons with (SeCN)3(-) ions in the electrolyte through its POEI-I segments. Thus, the POEI-IS renders a high open-circuit voltage (VOC) to the QSS-DSSC due to its functions of b-d and prolongs the stability of the cell due to its function of a. The QSS-DSSC with the gel electrolyte containing 30 wt % of the POEI-IS in liquid selenocyanate electrolyte exhibited a high VOC of 825.50 ± 3.51 mV and a high power conversion efficiency (η) of 8.18 ± 0.02%. The QSS-DSSC with 30 wt % POEI-IS retained up to 95% of its initial η after an at-rest stability test with the period of more than 1,000 h.

DOI: 10.1021/acsami.6b02767

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Cite this paper

@article{Lin2016MultifunctionalIP, title={Multifunctional Iodide-Free Polymeric Ionic Liquid for Quasi-Solid-State Dye-Sensitized Solar Cells with a High Open-Circuit Voltage.}, author={Yi-Feng Lin and Chun-Ting Li and Chuan-Pei Lee and Yow-An Leu and Yamuna Ezhumalai and Ragini Vittal and Ming-Chou Chen and Jiang-Jen Lin and Kuo-Chuan Ho}, journal={ACS applied materials & interfaces}, year={2016}, volume={8 24}, pages={15267-78} }