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

Abstract

In recent years dye-sensitized solar cells (DSSCs) have emerged as one of the alternatives for the global energy crisis. DSSCs have achieved a certified efficiency of >11% by using the I(-) /I3 (-) redox couple. In order to commercialize the technology almost all components of the device have to be improved. Among the various components of DSSCs, the redox couple that regenerates the oxidized sensitizer plays a crucial role in achieving high efficiency and durability of the cell. However, the I(-) /I3 (-) redox couple has certain limitations such as the absorption of triiodide up to 430 nm and the volatile nature of iodine, which also corrodes the silver-based current collectors. These limitations are obstructing the commercialization of this technology. For this reason, one has to identify alternative redox couples. In this regard, the Co(II/III) redox couple is found to be the best alternative to the existing I(-) /I3 (-) redox couple. Recently, DSSC test cell efficiency has risen up to 13% by using the cobalt redox couple. This review emphasizes the recent development of Co(II/III) redox couples for DSSC applications.

Recent Advances in Dual‐Functional Devices Integrating Solar Cells and Supercapacitors

“…Thus, for PSs, choosing new capacitative materials with novel nanostructures is an effective strategy to increase their specific capacitance. The working voltage of the PSs depends on the V oc of the PC part, while for DSSCs and QDSSCs the V oc depends on the difference between the Nernst potential of the redox electrolyte and the Fermi level of the oxide semiconductor …”

“…The working voltage of the PSs depends on the V oc of the PC part, while for DSSCs and QDSSCs the V oc depends on the difference between the Nernst potential of the redox electrolyte and the Fermi level of the oxide semiconductor. [125] Thus, for the DSSCs and QDSSCs serving as a PC part, choosing the proper electrolyte is a promising strategy to increase the V oc of the PC part. For the polymer solar cells, the V oc depends on the difference between the HOMO energy level of the electron donor and the LUMO energy level of the acceptor.…”

μ2-Chlorido-chlorido(μ2-4-{[2-(diethylamino)ethyl]imino}pent-2-en-2-olato)bis(tetrahydrofuran-κO)cobalt(II)lithium

“…Several synthetic approaches based on organic (Sauvage, 2014), inorganic (Bergeron et al, 2005;Burschka et al, 2012;Carli et al, 2013), or organometallic compounds (Carli et al, 2016;Spokoyny et al, 2010;Sun et al, 2015;Magni et al, 2016) have been reported with [Co(bpy) 3 ] 2+/3+ and [Co(phen) 3 ] 2+/3+ (where bpy = 2,2 0 -bipyridine and phen = 1,10-phenanthroline) as redox couples. Notably, DSSCs using cobalt redox pairs mostly tether to pyridine-type ligands with complex formal charge (2+/3+) (Ben Aribia et al, 2013;Lee et al, 2015;Bella et al, 2016;Kashif et al, 2013;Pashaei et al, 2015;Giribabu et al, 2015), displaying few structural deviations mainly by varying the ligand backbone with groups of different donating/withdrawing data reports ability (Pashaei et al, 2015;Xu et al, 2013), and without nonneutral ligands in the coordination sphere.…”

Spontaneous solar water splitting by DSSC/CIGS tandem solar cells

“…The dye-sensitized solar cell (DSSC) is attractive because the V oc of a DSSC can be adjusted from the difference between the Fermi level of the photoanode and the potential of the redox electrolyte (Li et al, 2015;Wu et al, 2016;Yum et al, 2012). A cobaltpolypyridine complex-based redox couple generates a high V oc of 0.8-1.0 V unlike the traditional I À /I 3 À redox couple, and shows excellent stability (Giribabu et al, 2015). In addition, its simple and solution-based fabrication method is compatible with tandem cell fabrication with inorganic solar cells, such as chalcopyrite solar cells, which is another promising material for tandem cell applications due to its tunable band gap (Kaelin et al, 2004).…”