Abstract
A new cobalt-terpyridine redox shuttle based on a substituted terpyridine ligand, has been synthesized, characterized, computationally investigated and tested in photovoltaic devices. The new redox shuttle is compared to the reference [Co(bpy)3]2+/3+, analyzing the effect of different counterions.
•Synthesis and characterization of a [Co(Cl-phenyl-terpy)2]2+/3+ redox couple.•Good agreement between experimental and calculated redox potentials.•Photovoltaic efficiency compared to the [Co(bpy)3]2+/3+ electrolyte with different counterions.•Improvement of the photovoltaic performances by using the CDCA additive.
A new cobalt-terpyridine redox shuttle ([Co(Cl-phenyl-terpyridine)2]2+/3+) has been synthesized, characterized, computationally investigated and then tested in photovoltaic devices, in conjunction with the prototypical N719 and Z907 ruthenium dyes. Lower efficiencies compared to the reference [Co(bpy)3]2+/3+ redox couple were obtained, probably due to increased recombination processes. Improvements in the devices performances were obtained by using chenodeoxycholic acid as surface co-adsorbent and as an electrolyte additive. Moreover, to better rationalize the photovoltaic results, the effect of two different counterions (TFSI and PF6) has been investigated for the reference [Co(bpy)3]2+/3+ electrolyte, finding a reduced efficiency for the TFSI-based electrolyte.