Novel D–π–A structured Zn(ii)-porphyrin dyes containing a bis(3,3-dimethylfluorenyl)amine moiety for dye-sensitised solar cells

Abstract

A high solar-to-electricity conversion efficiency of 7.22% was achieved with a short circuit current (J(sc)) of 15.30 mA cm(-2), an open circuit voltage (V(oc)) of 669 mV and a fill factor (FF) of 0.71 for the 2Flu-ZnP-CN-COOH dye with a multi-functional co-adsorbent, under 100 mW cm(-2) AM 1.5 G simulated light.

Organic Sensitizers Featuring a Planar Indeno[1,2‐b]‐thiophene for Efficient Dye‐Sensitized Solar Cells

“…The efficiency of 8.52 % in the JK-306sensitized cell was slightly improved (J sc = 16.14 mA cm À2 , V oc = 0.75 V, and ff = 0.71) compared to that of the JK-306-sensitized cell with CDCA, which should be attributed to the role of HC-A having multifunctional effects, [25][26][27] such as preventing dye aggregation, a light harvesting effect in the shorter wavelength regions around 360 nm, and fast dye regeneration through the hole conducting effect. Under the same conditions, the JK-306-sensitized cell gave rise to a J sc of 14.10 mA cm À2 , V oc of 0.75 V, and ff of 0.70, which afforded h of 8.37 %.…”

“…The respective Nyquist plots are presented in Figure S4. [25][26][27] The longer electron lifetime contributed to a higher open-circuit voltage (V oc ). There was no noticeable difference in C m between JK-306 solar cells based on HC-A and CDCA.…”

“…Two major factors for the low efficiency of organic DSSCs are the formation of dye aggregation on the TiO 2 surface [5,6] and interfacial charge recombination. In addition, the co-adsorption of dyes with additives, such as decylphosophonic acid, [22] dineohexyl bis(3,3-dimethylbutyl)phosphinic acid, [23] chenodeoxycholic acid (CDCA), [24] and 4-[bis (9,9-dimethyl-9H-fluoren-2-yl)amino]benzoic acid (HC-A), [25][26][27] is proven to be effective in dissociating p-p stacking or dye aggregation. [12] Our concept toward a high photovoltaic performance with organic DSSCs is based on the interface engineering of a dye-adsorbed TiO 2 surface controlled by the structural modification of the sensitizer to diminish the charge recombination and to prevent the aggregation of sensitizers.…”

Role of Co‐Sensitizers in Dye‐Sensitized Solar Cells

“…2Flu-ZnP-CN-COOH with CDCA as ac o-adsorbent and HCA1 as ac o-sensitizer. [58] Interestingly,the PCE of 2Flu-ZnP-CN-COOH + HCA1 (J SC = 15.30 mA cm À2 , V OC = 669 mV,F F = 0.71, and PCE = 7.22 %) was highert han 2Flu-ZnP-CN-COOH + CDCA (J SC = 14.59 mA cm À2 , V OC = 628 mV,F F = 0.72, and PCE = 6.64 %) owing to greaterr etardation of charger ecombination with HCA1 (CR1m echanism). Thus, the co-sensitized devices showedc onsiderable improvementi np hotovoltaic parameters relative to co-adsorbentsalone.…”

Dye‐Sensitized Solar Cells based on Organic Dual‐Channel Anchorable Dyes with Well‐Defined Core Bridge Structures

“…To effectively suppress dye aggregation for DSSCs, as in our previous study, [21][22][23][24][25][26] coadsorbents such as DCA and HC-A1 were used. Both the open circuit voltage (V oc ) and short circuit photocurrent density (J sc ) were dramatically enhanced by the coadsorption of the multifunctional HC-A1 with the dye, due to the efficient retardation of charge recombination arising from the p-p stacking, light harvesting in shorter wavelength regions, and a hole-conducting function through a redox cascade process.…”