Design of Truxene-Based Organic Dyes for High-Efficiency Dye-Sensitized Solar Cells Employing Cobalt Redox Shuttle

Abstract

Developing photosensitizers with high extinction coefficients, proper electronic structures, and steric properties is warranted for the dye-sensitized solar cells (DSCs) employing one-electron outer-sphere redox shuttles. DSCs incorporating Co(II/III)tris(1,10-phenanthroline)based redox electrolyte and three synthesized organic dyes as photosensitizers (M14, M18, and M19) are described. The hexapropyltruxene group on the dyes retards the rate of interfacial back electron transfer from the conduction band of the nanocrystalline titanium dioxide film to the [Co(III)-(phenanthroline) 3 ] 3+ ions, which enables attainment of high photovoltages approaching 0.9 V. The measurement of photocurrent transients shows that the mass transport limitation of the cobalt redox shuttle has been largely removed by using thin TiO 2 films. DSCs sensitized with M14 in combination with the cobalt redox shuttle yield a DSC with an overall power conversion efficiency (PCE) of 7.2% under 100 mW cm −2 AM1.5 G illumination. The influences of the dye structure on the performance of DSCs were also investigated.

Molecular engineering of carbazole-fluorene sensitizers for high open-circuit voltage DSSCs: Synthesis and performance comparison with iodine and cobalt electrolytes

“…corresponding overall photovoltaic data are given in Table 2. is higher than many of those reported for triarylamine [23,[29][30] or truxene [31,32] dyes in the presence of cobalt-based electrolyte and very close to that described for the C220 dye [33] which is one of the most efficient organic dyes reported so far in DSSCs. However, for each dye, the current density of thin-film devices including cobalt-based electrolytes remained lower than those measured for devices fabricated with Z960 electrolyte.…”

Recent Advances of Cobalt(II/III) Redox Couples for Dye‐Sensitized Solar Cell Applications

“…As discussed above, developing photosensitizers with high extinction coefficients and the appropriate electronic structures and steric properties is warranted for DSSCs employing one‐electron outer‐sphere cobalt redox shuttles. DSSCs incorporating Co(II/III)–tris(1,10‐phenanthroline)‐based redox electrolyte and truxene‐based organic dyes (e.g., M14 , M15 , M16 , M18 , M19 , and M20 ) as photosensitizers were described by Zong et al, who reported that the photovoltaic performance of the redox electrolyte based on [Co(phen) 3 ] 3+/2+ was superior to that of the iodide/triiodide redox shuttle for thin‐film DSSCs sensitized with these organic sensitizers (Table ) . The bulky hexapropyltruxene group on the dyes retards the rate of interfacial recombination of electrons from the conduction band of the nanocrystalline TiO 2 film to the Co(III) ions, which enables the attainment of high V OC values up to 0.9 V. The measurement of photocurrent transients shows that the mass transport limitation of the cobalt redox shuttle can be largely removed by using thin TiO 2 films.…”

A cascaded QSAR model for efficient prediction of overall power conversion efficiency of all-organic dye-sensitized solar cells

“…[6] and [18], published by Chen and coworkers and Mishra et al, [25] FULL PAPER WWW.C-CHEM.ORG in which the authors reviewed more than 200 pieces of literature and collected information on approximately 400 organic dye sensitizers in DSSCs with a TiO 2 film and liquid electrolyte. [6], [18][19][20][21] Most of these sensitizers are arylamine organic dyes that, as of now, are the most promising all-organic sensitizers with a high PCE. In the database preparation, the databases were carefully checked and the preprocesses included following steps: (1) removing the dyes lacking the observed parameters (J SC , V OC , FF, PCE) in the resources (Refs.…”