Multiple-Anchoring Triphenylamine Dyes for Dye-Sensitized Solar Cell Application

Abstract

A series of triphenylamine-based dyes (TPACR1, TPACR2, and TPACR3) with multiple corhodanine derivatives as acceptors were prepared and examined as sensitizers for dye-sensitized solar cells. The overall conversion efficiencies of DSSCs based on these dyes were in the range of 2.63 to 5.31%, in which TPACR2-based DSSC showed the best photovoltaic performance: a short-circuit current (Jsc) of 15.03 mA·cm–2, an open-circuit voltage (Voc) of 552 mV, and a fill factor (FF) of 0.64, corresponding to an overall efficiency of 5.31% under simulated AM 1.5 solar irradiation (100 mW·cm–2). Compared with monoanchoring TPACR1 dye and trianchoring TPACR3 dye, dianchoring TPACR2 dye had a relatively slower charge recombination rate between injected electrons and triphenylamine dye cations, which was indicated by transient absorption kinetics Furthermore, the suppression of the charge recombination between injected electron and the I3– in the electrolyte lead to the longer electron lifetime observed with the DSSC based on the TPACR2 dye. In comparison with the TPACR1 and TPACR3 dye, the TPACR2 dye showed the higher overall conversion efficiency with simultaneous enhancement of photocurrent and photovoltage.