A new terpyridine cobalt complex redox shuttle for dye-sensitized solar cells

Abstract

A new cobalt-terpyridine redox shuttle ([Co(Cl-phenyl-terpyridine) 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 PF 6 ) has been investigated for the reference [Co(bpy) 3 ] 2+/3+ electrolyte, finding a reduced efficiency for the TFSI-based electrolyte.GRAPHICAL ABSTRACT

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

“…The simple Co III/II terpyridine redox couple exhibits a redox potential of 0.51 V versus NHE . Introduction of an electron‐withdrawing Cl group to the terpyridine moiety results in an increase of the standard potential to 0.603 V versus NHE, but introduction of a chlorophenyl substituent results in a decrease of the standard potential to 0.474 V versus NHE …”

“…The Cl‐phenyl‐terpyridine cobalt complex [Co(Cl‐phen‐tpy) 2 ] shows a redox potential of 0.474 V versus NHE, which is slightly less positive than the oxidation potential of cobalt bipyridine [Co(bpy) 3 ] (0.56 V vs NHE) and terpyridine [Co(tpy) 3 ] complexes (0.51 V vs NHE) and is also less positive than the oxidation potential of the Cl‐terpyridine cobalt complex (0.603 vs NHE). This can be rationalized by the screening effect of the intervening phenyl moiety, which separates the terpyridine core from the electron‐withdrawing chloride.…”

“…Filippo DeAngelis and co‐workers have reported a combined experimental and computational investigation to understand the nature of the interactions between cobalt redox mediators and TiO 2 surfaces sensitized by ruthenium and organic dyes, and their impact on the performance of the corresponding DSSCs . They used ruthenium and organic dyes to understand the dramatic loss of efficiency observed for the prototype Ru(II) dye N719 in conjunction with cobalt electrolytes.…”

Co‐sensitized cells from Antarctic resources using Ag nanoparticles

“…Based on the use of coloured dyes as photosensitizers, they can harvest the light in the visible range of the spectrum to generate an electric current. [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15] The cells contain a nanoporous oxide layer, which offers a surface to attach the dyes that adsorb the light, and the energy used to excite an electron into the conduction band of the oxide layer.…”

Thiocyanate functionalized ionic liquid electrolyte for photoelectrochemical study of cadmium selenide pebbles

“…Yang and co-workers [18] used Na 2 S based electrolyte for CdS solar cells. A new terpyridine cobalt complex redox shuttle electrolyte is used for DSSCs [19]. We have used the polysulfide and thiocyanate IL based electrolytes to study photoelectrochemical performance of CdSe pebbles.…”